tcec practical hard mate test

[Uri Blass]

For me the interesting question is what it is that makes these positions so tough for engines.
High number of legal moves, in general? Tactics? Promotions? (which most likely leads to problem #1)
Bad move ordering for this type of problems?

There isn't any type of problems arising in game playing of course, "type" of "such" postions depending on the game leading to them. As many games as can be searched for DTM- positions, as many as that there are "such" positions arising sooner or later.
Difference as for TCEC- games is only the hardware- time used for game playing there, so you see DTM- outputs arising sooner.

And to let engines ponder started with empty hash is waste of hardware- time with "such" positions anyhow too, you won't be able to compare such results with the outputs of engines playing these games, cause those have much time to fill their hash with pondering step by step nearer and nearer to mate in game playing too, on the other hand, engines at game playing don't have best settings for search of DTM, e.g. NNUE- engines most of the time get longer DTM- outputs sooner without usage of NNUE- eval, Syzaygys (or other tbs without DTM- info stored) are most of times better switched off too.

Forward- Backward solves "such" positions much faster with all engines you try, at least you can rely much faster on DTM for "solution", the point of "finding" the (provable?) DTM depends simply on starting- position some nearer or some further away from mate.
Or to ask shorter again: how to know for such long DsTM, "solution" found is the very right one without giving Forward- Backward a try too?

Just my two cents regards

Not always forward backward solve the positions faster and there are cases when without forward backward the engine can find a different better move that without it you do not analyze it for enough time.

[peter]

Not always forward backward solve the positions faster and there are cases when without forward backward the engine can find a different better move that without it you do not analyze it for enough time.

Could you show any example?

Not so easy of course to measure time of Forward- Backward, what I meant was interactive one of a somewhat experienced user.

But also as for stand-alone pondering started with empty hash: as for positions of long DsTM, there's much difference in time to "solution" with SMP-trials of course too, and if you want to test single threaded only, I'd advise for Forward- Backward here even more, if you want to find shortest DTM in reasonable time.
Or you just take engines that aren't made for game playing like Chest or Gustav too, working single threaded only at all, but these are somewhat uncomparable then at all, as well as it's also the point as for engines with option of DTM- search to be checked or unchecked.

As the saying goes: no rule without exception regards

[Uri Blass]

Next position is hard for slowchess that finally declared mate in 31.
In the game after Nxc7 stoofvless blundered by Qxc7 and did not play Rc8

FEN: r4n1k/p1p1q3/PpP1Pb1r/1N1Qp3/1P2PpR1/5N1p/1K5P/6R1 w - - 7 1 bm Nxc7 dm 31

Slow64-avx2 [001]:
2/3 00:00 3k 0 +5.68 Rg4-g8+ Kh8-h7 Kb2-b3
3/5 00:00 9k 0 +4.12 Rg4-g8+ Kh8-h7 Kb2-b3 Ra8-d8
4/7- 00:00 12k 0 +3.72 Rg4-g8+ Kh8-h7
4/7- 00:00 19k 0 +2.92 Rg4-g8+ Kh8-h7
4/7 00:00 25k 0 +2.00 Rg4-g8+ Kh8-h7 Qd5-b3 Ra8-d8 Nb5xa7 Qe7xe6
4/7+ 00:00 26k 0 +3.73 Nb5xc7
4/7- 00:00 27k 0 +1.32 Nb5xc7 Ra8-d8
4/7 00:00 27k 0 +2.00 Rg4-g8+ Kh8-h7 Qd5-b3 Ra8-d8 Nb5xa7 Qe7xe6
5/8+ 00:00 34k 0 +2.32 Rg4-g8+
5/8 00:00 36k 0 +2.36 Rg4-g8+ Kh8-h7 Qd5-c4 Ra8-d8 Nb5xa7 Qe7xe6
5/8+ 00:00 38k 0 +2.96 Nb5xc7
5/8+ 00:00 39k 0 +4.24 Nb5xc7
5/8 00:00 41k 0 +4.68 Nb5xc7 Ra8-d8 Qd5-b3 Kh8-h7 Nc7-d5 Qe7xe6
6/8 00:00 46k 0 +4.84 Nb5xc7 Qe7xc7 e6-e7 Nf8-g6 Rg4xg6 Rh6xg6 Rg1xg6 Qc7xe7
7/9- 00:00 50k 0 +4.37 Nb5xc7 Qe7xc7
7/10- 00:00 60k 0 +3.43 Nb5xc7 Ra8-c8
7/10 00:00 76k 7,615k +2.68 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4xe4 c6-c7 Qe4-e2+ Qb3-c2+
8/10+ 00:00 94k 9,411k +3.06 Nb5xc7
8/10 00:00 95k 9,461k +3.06 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4xe4 e6-e7 Qe4-e2+ Kb2-b1
8/10 00:00 101k 10,121k +3.16 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4xe4 c6-c7 Qe4-e3 Qb3xe3 f4xe3
8/10+ 00:00 102k 10,197k +3.17 Rg4-g8+
9/17+ 00:00 144k 7,193k +3.59 Nb5xc7
9/17 00:00 147k 7,353k +2.84 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4xe4 e6-e7 Qe4-e2+ Kb2-b1
9/17+ 00:00 149k 7,440k +2.85 Rg4-g8+
9/17 00:00 156k 5,184k +2.85 Rg4-g8+ Kh8-h7 Qd5-c4 Ra8-d8 Nb5xa7 Qe7xe6 Qc4xe6 Nf8xe6 Rg8xd8 Ne6xd8 Na7-b5 Nd8xc6 a6-a7
9/17 00:00 184k 6,146k +3.36 Rg4-g8+ Kh8-h7 Qd5-c4 Ra8-d8 Nb5xa7 Qe7xe6 Qc4xe6 Nf8xe6 Rg8xd8 Ne6xd8 b4-b5 Nd8-e6 Na7-c8 Ne6-c5
9/17+ 00:00 186k 6,195k +3.37 Nb5xc7
9/17+ 00:00 200k 6,672k +4.45 Nb5xc7
9/17 00:00 201k 6,692k +2.84 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4xe4 e6-e7 Qe4-e2+ Kb2-b1
9/17+ 00:00 201k 6,700k +3.36 Rg4-g8+
9/19 00:00 258k 5,151k +4.84 Rg4-g8+ Kh8-h7 Qd5-c4 Ra8-d8 Nb5xa7 Bf6-h4 Nf3xh4 Rh6xh4 Na7-b5 Nf8xe6 a6-a7 Rd8xg8 Rg1xg8 Kh7xg8 a7-a8Q+ Kg8-h7
9/19 00:00 366k 5,234k +2.85 Rg4-g8+ Kh8-h7 Qd5-c4 Rh6-h5 Kb2-c2 Ra8-d8 Nb5xa7 Qe7xe6 Qc4xe6 Nf8xe6 Rg8xd8 Bf6xd8 Na7-c8
9/19+ 00:00 368k 5,255k +2.86 Nb5xc7
9/19 00:00 384k 5,479k +5.69 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Bf6-h8 Qb3-c4 Rh6xe6 Nf3-g5+
10/19 00:00 424k 5,301k +5.93 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Bf6-h8 Kb2-b1 Rh6xe6 Nb5xa7 Rc8xc7 Nf3-g5+
11/19 00:00 453k 5,029k +5.76 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 Qb3-c4 Bf6-h8 Nb5xa7 Rc8-c7 Na7-b5 Nf8xe6 Nb5xc7 Qe7xc7 Qc4-b4
12/24+ 00:00 642k 4,937k +6.66 Nb5xc7
12/24 00:00 653k 5,026k +6.24 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Bf6-h8 Kb2-b1 Rh6-f6 Qb3-c4 Rf6xe6 Nf3-g5+ Kh7xg8 Ng5xe6+ Kg8-h7 Ne6xf8+ Qe7xf8 Nb5xa7
12/24 00:00 801k 5,003k +6.84 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Rh6-h5 Qb3-c4 Rh5-h6 Kb2-b1 Bf6-h4 Rg1-g7+ Qe7xg7 Rg8xg7+
13/25 00:00 956k 4,780k +6.72 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Rh6-h5 Qb3-c4 Rh5-h6 Kb2-b1 Rh6-h5 Kb1-c2 Rh5-h6 Kc2-b3 Rh6-h5 Rg8xf8 Qe7xf8 Nb5xa7 Bf6-e7 Na7xc8
14/26 00:00 1,362k 4,865k +7.00 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-h5 c6-c7 Rd8-c8 Qb3-c4 Rh5-h6 Kb2-b1 Rh6-h5 Kb1-c2 Rh5-h6 Rg8xf8 Qe7xf8 Nb5xa7 b6-b5 Na7xb5
15/28 00:00 2,032k 5,080k +7.44 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xc8 Qe7xb4+ Kb2-c2 Ng6-e7 Rc8-c7 Kh7-h6 Qd5-d3 Qb4-a4+ Kc2-d2 Qa4-a2+ Kd2-e1 Qa2-a1+ Ke1-e2
15/28+ 00:00 2,250k 5,232k +7.45 Rg4-g8+
16/29 00:00 4,505k 5,363k +8.00 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8xc6 Qd5xc6 Qe7xb4+ Kb2-c1 Rh6-g6 Rg8xg6 Nf8xg6 Qc6-e8 Qb4xe4 Qe8-f7+ Kh7-h6 Qf7xf6 Qe4-c4+ Kc1-d2 Qc4-a2+ Kd2-d3 Qa2-d5+ Nf3-d4 e5-e4+ Kd3-d2 Qd5-a2+ Kd2-c3 Qa2-a5+ Kc3-b3
17/29 00:01 5,877k 5,343k +7.16 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5xd8 Qe7xd8 c6-c7 Qd8-e8 c7-c8Q Qe8xc8 e6-e7 Rh6-g6 e7xf8Q Qc8xf8 Rg8xf8 Rg6xg1 Nf3xg1 Kh7-g7
18/29+ 00:01 6,690k 5,395k +8.42 Nb5xc7
18/31 00:01 8,472k 5,466k +7.64 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Rh6-h5 Qb3-c4 Rh5-h6 Kb2-b1 Bf6-h8 Rg8xf8 Rc8xf8 Nf3-g5+ Kh7-g6 Ng5-f7+ Kg6-h7 c7-c8Q Rf8xc8 Qc4xc8
18/32 00:02 14,550k 5,511k +8.52 Nb5xc7 Ra8-d8 Qd5-c4 b6-b5 Nc7xb5 Qe7xe6 Qc4xe6 Nf8xe6 c6-c7 Ne6xc7 Nb5xc7 Rh6-h5 Nc7-d5 Rd8xd5 e4xd5 e5-e4+ Kb2-b3 Rh5-f5 Rg4-g6 Kh8-h7 Rg6xf6 Rf5xf6 Nf3-g5+ Kh7-h6 Ng5xe4 Rf6xa6
19/35 00:03 18,607k 5,538k +9.16 Nb5xc7 Ra8-d8 Qd5-c4 b6-b5 Nc7xb5 Qe7xe6 Qc4xe6 Nf8xe6 c6-c7 Ne6xc7 Nb5xc7 Kh8-h7 Nc7-d5 Rd8xd5 e4xd5 e5-e4+ Kb2-b3 e4xf3 Rg4xf4 Bf6-e5 Rf4-f7+ Kh7-h8 Rf7xf3 Be5xh2 Rg1-h1 Kh8-g7 Rh1xh2
20/35- 00:05 27,980k 5,585k +8.09 Nb5xc7 Ra8-c8
20/35+ 00:05 29,845k 5,589k +9.58 Nb5xc7
20/36 00:06 36,108k 5,624k +9.65 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xc8 Qe7xb4+ Kb2-c1 Ng6-e7 Rc8-c7 Qb4-a4 Rc7xa7 Kh7-g6 Nf3xe5+ Kg6-h6 Ra7xe7 Qa4-a1+ Kc1-c2 Qa1-a4+ Qd5-b3 Qa4xe4+ Qb3-d3 Qe4-g2+ Kc2-c3 Bf6xe7 a6-a7
20/41 00:10 57,511k 5,666k +9.88 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8xc6 Qd5xc6 Qe7xb4+ Kb2-c1 Rh6-g6 Rg8xg6 Nf8xg6 e6-e7 Qb4xe7 Qc6-b7 Kh7-h6 Qb7xe7 Bf6xe7 Nb5xa7 Be7-c5 Rg1-f1 Ng6-e7 Nf3xe5 Kh6-g7 Kc1-c2 f4-f3 Na7-b5 f3-f2
21/44 00:15 86,556k 5,728k +11.04 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 c6-c7 Rh6-h5 Qb3-c4 Rh5-h6 Kb2-b3 Bf6-h8 Rg8xf8 Rc8xf8 Nb5xa7 b6-b5 Na7xb5 Rh6-f6 Nf3-g5+ Kh7-h6 Ng5-f7+ Kh6-h7 c7-c8Q Rf6xf7 e6xf7 Rf8xc8 Qc4xc8 Qe7xf7+ Kb3-b4 Bh8-g7 Qc8xh3+ Bg7-h6 a6-a7
22/44 00:28 159,317k 5,688k +12.04 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Qe7xe6 Nb5xa7 Qe6xb3+ Kb2xb3 Nf8-e6 Rg8xd8 Bf6xd8 Na7-b5 Ne6-c5+ b4xc5 Rh6xc6 a6-a7 Rc6-c8 c5-c6 Rc8-a8 Nf3xe5 f4-f3 Ne5xf3 Kh7-h6 Nf3-e5 Kh6-h7 Rg1-g6 Bd8-e7 c6-c7 Be7-c5 Nb5-d6 Bc5xd6 Rg6xd6
23/45- 00:30 174,665k 5,727k +10.36 Nb5xc7 Ra8-c8
23/45 00:33 194,598k 5,762k +12.28 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xc8 Qe7xb4+ Kb2-c1 Ng6-e7 Rc8-c7 Qb4-a4 Rc7xa7 Kh7-g6 Nf3xe5+ Kg6-h6 Ne5-g4+ Kh6-g6 Ra7xe7 Qa4-a1+ Kc1-c2 Qa1-b2+ Kc2-d3 Qb2-b1+ Kd3-e2 Qb1-c2+ Ke2-f3 Qc2-g2+ Kf3xf4 Qg2-f1+ Kf4-e3 Bf6xe7
24/45- 00:33 195,173k 5,762k +10.54 Nb5xc7 Ra8-c8
24/45 00:47 278,769k 5,880k +12.98 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Nf8-g6 Rg8xd8 Qe7xd8 c6-c7 Qd8-f8 Nb5xa7 Ng6-e7 Qb3-c4 b6-b5 Qc4xb5 Rh6-g6 Rg1xg6 Kh7xg6 Na7-c6 Ne7xc6 Qb5xc6 Qf8xb4+ Kb2-c2 Qb4-a3 c7-c8Q Qa3xf3 e6-e7 Qf3-e2+ Kc2-c3 Qe2-e3+ Kc3-c4 Qe3-d4+ Kc4-b3 Qd4-d1+ Kb3-b4 Qd1-d2+ Kb4-c5 Qd2-a5+
25/49- 00:59 355,897k 5,974k +11.06 Nb5xc7 Ra8-c8
25/49 01:04 383,049k 5,954k +10.32 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 Nb5-d6 Rc8xc6 Nd6-f5 Qe7xe6 Rg8xf8 Qe6xb3+ Kb2xb3 Rh6-h5 Rf8-f7+ Kh7-h8 Rf7xa7 Rh5xf5 e4xf5 e5-e4 Nf3-g5 Bf6xg5 Ra7-b7 Rc6-c5 a6-a7 Rc5-a5 Rg1xg5 Ra5xa7 Rb7xa7 f4-f3 Rg5-h5+ Kh8-g8 Rh5xh3
26/52+ 01:16 454,261k 5,937k +12.69 Nb5xc7
26/52 01:48 656,616k 6,037k +13.20 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xd8 Qe7xd8 c6-c7 Qd8-e8 Qb3-c4 Ng6-e7 Nb5xa7 b6-b5 Na7xb5 Qe8-h5 a6-a7 Qh5xf3 a7-a8Q Qf3-h1 Qc4-c2 Qh1-e1 c7-c8Q Ne7xc8 Qa8xc8 Qe1xb4+ Qc2-b3 Qb4-d2+ Qc8-c2 Qd2-d8 Qb3xh3+ Kh7-g8 Qh3-f5 Kg8-f8
26/55 01:58 717,618k 6,071k +12.64 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Qe7xe6 Nb5xa7 Qe6xb3+ Kb2xb3 Nf8-e6 Rg8xd8 Bf6xd8 Na7-b5 Ne6-c5+ b4xc5 Rh6xc6 a6-a7 Rc6-c8 c5-c6 Rc8-a8 Nf3xe5 f4-f3 Ne5xf3 Kh7-h8 Nf3-g5 Bd8xg5 Rg1xg5 Kh8-h7 Rg5-h5+ Kh7-g6 Rh5xh3
27/55 02:29 930,149k 6,214k +15.68 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Qe7xe6 Nb5xa7 Qe6xb3+ Kb2xb3 Nf8-e6 Rg8xd8 Bf6xd8 Na7-b5 Ne6-c5+ b4xc5 Rh6xc6 a6-a7 Rc6-c8 c5-c6 Rc8-a8 Nf3xe5 f4-f3 Ne5xf3 Kh7-h8 Nf3-g5 Bd8-e7 Ng5-e6 Be7-f6 Ne6-c7 Ra8xa7 Nb5xa7 Kh8-h7 Nc7-d5 Bf6-e5 c6-c7 Be5xc7 Nd5xc7 Kh7-h6
28/57 04:40 1,761,593k 6,289k +17.04 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Qe7xe6 Nb5xa7 Qe6xb3+ Kb2xb3 Nf8-e6 Rg8xd8 Bf6xd8 Na7-b5 Ne6-c5+ b4xc5 Rh6xc6 a6-a7 Rc6-c8 c5-c6 Rc8-a8 Nf3xe5 Ra8xa7 Nb5xa7 Bd8-c7 Ne5-f7 Bc7-b8 Na7-b5 f4-f3 Nf7-g5+ Kh7-g7 Ng5xf3+ Kg7-f8 c6-c7 Bb8xc7 Nb5xc7 Kf8-f7 Nc7-d5 b6-b5 Nf3-g5+ Kf7-e8 Ng5xh3 Ke8-d7 Nh3-f4
29/57 10:23 4,029,261k 6,460k +20.32 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xc8 Qe7xb4+ Kb2-c1 Qb4-a4 Rc8-c7+ Kh7-h6 Rc7xa7 Qa4-a1+ Kc1-c2 Qa1-a4+ Kc2-b2 Qa4-b4+ Kb2-c1 Qb4-a4 Ra7-f7 Bf6-e7 c6-c7 Be7-a3+ Nb5xa3 Qa4xa3+ Kc1-c2 Qa3xf3 c7-c8Q Qf3-e2+ Qd5-d2 Qe2xe4+ Kc2-b2 Qe4-g2 Qd2-c2 e5-e4 a6-a7 e4-e3 e6-e7 Qg2xc2+ Kb2xc2
30/57 19:04 7,646,265k 6,678k +22.36 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rd8-c8 c6-c7 Rh6-h5 Qb3-c4 Rh5-h6 Kb2-b3 Rh6-h5 Qc4-c6 Rh5-h6 Qc6-d5 Rc8xc7 Nb5xc7 Rh6-g6 Rg1xg6 Nf8xg6 Rg8-a8 Qe7xc7 Qd5-b7 Qc7-e7 Qb7xe7+ Ng6xe7 Ra8xa7 Kh7-h6 Ra7-c7 Kh6-h5 a6-a7 Kh5-g4 Nf3-d2 Bf6-h4 a7-a8Q Bh4-e1 Nd2-c4 Kg4-f3 Nc4xe5+ Kf3-e3 Rc7xe7 f4-f3 Re7-f7 f3-f2
31/61 39:53 15,791,198k 6,599k +21.64 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Qe7xb4+ Qd5-b3 Qb4-e7 Nb5xa7 Rc8-c7 Na7-b5 Rc7-c8 Nb5-d6 Rc8-c7 Nd6-f5 Qe7xe6 Nf5xh6 Qe6xb3+ Kb2xb3 Nf8-e6 Nh6-f5 Ne6-c5+ Kb3-c4 Nc5xe4 Rg1-g6 Rc7-a7 Kc4-b5 Ra7-f7 Kb5xb6 Bf6-d8+ Rg8xd8 Rf7xf5 Rg6-g8 Ne4-d6 a6-a7 Nd6-c4+ Kb6-c5 e5-e4+ Kc5xc4 Rf5-a5 c6-c7 Ra5xa7 c7-c8Q Ra7-a4+ Kc4-d5
32/63 1:13:57 28,767,256k 6,483k +27.92 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Rc8-d8 Qd5-b3 Nf8xg6 Rg8xd8 Qe7xd8 c6-c7 Qd8-h8 Nb5xa7 Ng6-e7 Qb3-c3 Qh8-g8 c7-c8Q Ne7xc8 Na7xc8 Qg8xe6 a6-a7 Qe6-g4 a7-a8Q Kh7-g7 Qa8-b7+ Kg7-h6 Qb7xb6 Qg4-g7 Qb6-e6 Qg7-g6 Qe6xh3+ Kh6-g7 Nf3xe5 Kg7-g8 Qh3-e6+ Kg8-h7 Qc3-c7+ Kh7-h8 Qe6-h3+ Kh8-g8 Nc8-e7+ Bf6xe7 Ne5xg6
33/68- 1:25:51 32,916,073k 6,389k +19.89 Nb5xc7 Ra8-c8
33/68 1:27:16 33,411,718k 6,381k +21.64 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-h5 c6-c7 Rd8-c8 Kb2-b1 Rh5-h6 Qb3-c4 Bf6-h8 Rg8xf8 Rc8xf8 Nb5xa7 b6-b5 Na7xb5 Rh6-f6 Nf3-g5+ Kh7-h6 Ng5-f7+ Kh6-h7 c7-c8Q f4-f3 Nf7-g5+ Kh7-h6 Qc8-c7 f3-f2 Rg1-f1 Qe7-g7 Qc7xg7+ Bh8xg7 Ng5xh3 Rf6-g6 Rf1xf2 Bg7-f6 Nb5-c7 Rf8-c8 a6-a7 Bf6-e7 Rf2-f7 Rg6-g7 Qc4-c1+ Kh6-h7 Nh3-g5+
34/68 1:52:33 42,236,543k 6,254k +29.84 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-h5 c6-c7 Rd8-c8 Qb3-c4 Rh5-h6 Kb2-b3 Rc8-a8 Qc4-c6 Ra8-c8 Qc6-d5 Rc8xc7 Nb5xc7 Rh6-g6 Rg8xg6 Nf8xg6 Qd5-b7 Kh7-h6 Qb7xa7 Qe7-h7 Qa7xb6 Ng6-h4 Nf3xh4 Qh7xe4 a6-a7 Kh6-h5 a7-a8Q Qe4-d3+ Kb3-a4 Qd3-c2+ Ka4-b5 Qc2-d3+ Kb5-c6 Qd3-e2 Nh4-f5 Qe2-c2+ Qb6-c5 Qc2-g2+ Rg1xg2 h3xg2 Qa8-g8 f4-f3 e6-e7
35/68 2:13:06 49,118,909k 6,150k +31.44 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-g6 Rg1xg6 Nf8xg6 Rg8xd8 Qe7xd8 c6-c7 Qd8-f8 Nb5xa7 Ng6-e7 Qb3-c3 Qf8-g8 c7-c8Q Ne7xc8 Na7xc8 Qg8-g2+ Kb2-b3 Qg2-f1 a6-a7 Qf1-b1+ Kb3-a3 Qb1xe4 e6-e7 Qe4-g6 a7-a8Q Kh7-h6 Nf3xe5 f4-f3 Ne5xg6 Bf6xc3 e7-e8Q Bc3-b2+ Ka3xb2 Kh6-g5 Qa8xf3
36/68+ 2:43:16 60,490,766k 6,174k +M249 Nb5xc7
36/68- 2:45:28 61,293,153k 6,173k +M250 Nb5xc7 Ra8-c8
37/68 2:46:17 61,633,876k 6,177k +30.16 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Qe7xe6 Nb5xa7 Qe6xb3+ Kb2xb3 Rd8-d3+ Kb3-c4 Rd3xf3 c6-c7 Rf3-g3 Rg1xg3 f4xg3 Rg8xg3 Bf6-h4 Rg3xh3 Nf8-e6 c7-c8Q Ne6-d4 Qc8-d7+ Kh7-g8 Qd7-e8+ Kg8-h7 Qe8-f7+ Kh7-h8 Rh3xh4 Rh6xh4 Qf7-f6+ Kh8-h7 Qf6xh4+ Kh7-g6 Qh4-g3+ Kg6-f7 Qg3xe5 Nd4-c2 Na7-c6 b6-b5+ Kc4xb5 Kf7-g6 a6-a7 Nc2-a3+ Kb5-c5 Kg6-h6 a7-a8Q
38/68+ 2:47:56 62,265,900k 6,179k +M249 Nb5xc7
38/72- 2:48:45 62,574,436k 6,180k +M250 Nb5xc7 Ra8-c8
39/74 3:57:38 87,755,566k 6,154k +40.56 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rc8-d8 Qd5-b3 Rh6-h5 c6-c7 Rd8-e8 Qb3-c4 Re8-c8 Kb2-b3 Rh5-h6 Qc4-d5 Rh6-h5 Qd5-c6 Rh5-h6 Qc6-c4 Bf6-h8 Nb5xa7 b6-b5 Na7xb5 Rh6-f6 a6-a7 Rf6xe6 Nf3-g5+ Kh7xg8 Ng5xe6+ Kg8-h7 Ne6-g5+ Kh7-g7 Ng5-f7+ Kg7-h7 Nf7-d6 Qe7-e6 Nd6xc8 f4-f3 Qc4xe6 Nf8xe6 a7-a8Q f3-f2 Rg1-f1 Bh8-f6 Rf1xf2 Kh7-g7 Nc8-d6 Bf6-g5 c7-c8Q Ne6-c5+ b4xc5 Bg5-f4 Rf2xf4
40/74+ 4:00:47 88,928,663k 6,155k +M249 Nb5xc7
40/74- 4:03:28 89,919,698k 6,155k +M250 Nb5xc7 Ra8-c8
41/74 4:43:52 104,436,570k 6,132k +M31 Nb5xc7 Ra8-c8 Rg4-g8+ Kh8-h7 Nc7-b5 Rh6-g6 Rg1xg6 Qe7xb4+ Qd5-b3 Nf8xg6 Qb3xb4 Rc8xg8 Nb5xa7 Ng6-e7 Qb4xb6 Ne7-d5 e4xd5 e5-e4+ Kb2-b3 e4xf3 Qb6-c7+ Kh7-h6 Qc7xf4+ Bf6-g5 Qf4xf3 Rg8-b8+ Kb3-c4 Rb8-b1 Qf3xh3+ Kh6-g7 d5-d6 Rb1-c1+ Kc4-b5 Rc1-b1+ Kb5-c5 Rb1-c1+ Kc5-b6 Rc1-c4 Qh3-g3 Kg7-f6 e6-e7 Bg5-f4 Qg3-h4+ Kf6-g7 e7-e8N+ Kg7-g6 Qh4-g4+ Bf4-g5 Qg4xc4 Bg5-e3+ Kb6-b7 Kg6-g5 c6-c7 Be3-f4 c7-c8Q Bf4-e3 Qc4-g8+

[Ignacio]

Hi Uri.

I have get mate in 25.

FEN: r4n1k/p1p1q3/PpP1Pb1r/1N1Qp3/1P2PpR1/5N1p/1K5P/6R1 w - - 7 1

Cfish_11a_popcnt_windows:
1/2 00:00 8.492 4.246.000 +M25 Cb5xc7
2/2 00:00 13.439 6.719.500 +M25 Cb5xc7 Ta8-d8
3/3 00:00 15.130 7.565.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3
4/4 00:00 20.079 10.039.500 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7
5/5 00:00 24.102 12.051.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5
6/6 00:00 30.680 15.340.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8
7/7 00:00 37.872 12.624.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7
8/8 00:00 49.317 16.439.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8
9/11 00:00 82.353 27.451.000 +8,84 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8
10/13 00:00 111.303 27.825.750 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7
11/12 00:00 121.659 30.414.750 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4
12/13 00:00 130.870 32.717.500 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3
13/14 00:00 142.796 28.559.200 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5
14/15 00:00 154.287 30.857.400 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8
15/16 00:00 169.095 33.819.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8
16/17 00:00 183.063 36.612.600 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D
17/18 00:00 199.467 33.244.500 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8
18/19 00:00 220.033 36.672.166 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8
19/20 00:00 243.315 34.759.285 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5
20/21 00:00 268.396 38.342.285 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5
21/22 00:00 290.199 41.457.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5
22/24 00:00 322.222 40.277.750 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5
23/26 00:00 359.114 39.901.555 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6
24/27 00:00 389.135 43.237.222 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7
25/29 00:00 424.625 47.180.555 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5
26/30 00:00 457.429 45.742.900 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1
27/31 00:00 509.706 46.336.909 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D
28/33 00:00 536.044 48.731.272 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4
29/35 00:00 585.203 48.766.916 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3
30/37 00:00 637.308 49.023.692 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3
31/38 00:00 689.007 49.214.785 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5
32/40 00:00 747.556 49.837.066 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8-g8+ Rg5-f6
33/42 00:00 5.383.230 81.564.090 +M29 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7
34/44 00:00 6.161.480 83.263.243 +M32 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6
35/46 00:00 7.047.357 84.907.915 +M31 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-d7+ Rg7-g6 Dd7-g4+ Rg6-f7
36/46 00:00 7.771.500 86.350.000 +M28 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-c7 Rg6-f7
37/48 00:00 8.674.472 87.620.929 +M28 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d6 f4-f3 De5-f5+ Rg6-g7
38/50 00:00 9.689.372 88.085.200 +M28 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d6 f4-f3 De5-f5+ Rg6-g7 Df5-g5+ Rg7-f8
39/52 00:00 10.823.341 89.449.099 +M28 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d6 f4-f3 De5-f5+ Rg6-g7 Df5-g5+ Rg7-f8 Dg5-f6+ Rf8-g8
40/54 00:00 12.367.167 90.935.051 +M28 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d6 f4-f3 De5-f5+ Rg6-g7 Df5-g5+ Rg7-f8 Dg5-f6+ Rf8-g8 Df6-g6+ Rg8-f8
41/54 00:00 13.882.246 91.935.403 +M27 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 c6-c7 Td8-c8 Tg4-g8+ Rh8-h7 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d4 f4-f3 De5-f5+ Rg6-g7 Cd4-e6+ Rg7-h6 Df5-g5+ Rh6-h7 Dg5-g7+
42/54 00:00 15.490.818 92.759.389 +M27 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d4 f4-f3 De5-f5+ Rg6-g7 Cd4-e6+ Rg7-h6 Df5-g5+ Rh6-h7 Dg5-g7+
43/54 00:00 17.495.622 94.062.483 +M27 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d4 f4-f3 De5-f5+ Rg6-g7 Cd4-e6+ Rg7-h6 Df5-g5+ Rh6-h7 Dg5-g7+
44/54 00:00 19.801.344 91.672.888 +M27 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 Dd5-e6+ Rh6-g7 De6xe5+ Rg7-h7 e7-e8D Dg1-b1+ Rb3-a3 Db1-c1+ De5-b2 Dc1xb2+ Ra3xb2 Rh7-g7 De8-e5+ Rg7-g6 Cb5-d4 f4-f3 De5-f5+ Rg6-g7 Cd4-e6+ Rg7-h6 Df5-g5+ Rh6-h7 Dg5-g7+
45/50 00:00 19.871.747 91.574.870 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
46/50 00:00 19.925.959 91.403.481 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
47/50 00:00 19.979.808 91.232.000 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
48/50 00:00 20.022.923 91.428.872 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
49/50 00:00 20.074.266 91.246.663 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
50/50 00:00 38.117.751 76.541.668 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
51/50 00:00 38.890.155 76.405.019 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
52/50 00:00 39.133.053 76.282.754 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
53/50 00:00 48.900.813 74.657.729 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
54/50 00:01 116.159.322 71.482.659 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
55/50 00:01 135.574.276 71.392.457 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
56/50 00:03 277.016.316 71.212.420 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
57/50 00:06 476.483.945 71.021.604 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+
58/50 00:10 751.928.857 70.544.033 +M25 Cb5xc7 Ta8-d8 Dd5-b3 Cf8-h7 Cc7-b5 Ch7-f8 Tg4-g8+ Rh8-h7 c6-c7 Td8-c8 Db3-c4 Th6-h4 Rb2-b3 Th4-h5 Tg8xf8 Tc8xf8 c7-c8D Tf8xc8 Dc4xc8 Th5-g5 Tg1xg5 Af6xg5 Cf3xg5+ De7xg5 Dc8-d7+ Rh7-h6 e6-e7 Dg5-g8+ Dd7-d5 Dg8-g1 e7-e8D Dg1-b1+ Rb3-a4 Db1-c2+ Dd5-b3 Dc2xb3+ Ra4xb3 Rh6-g5 De8xe5+ Rg5-g6 Cb5-d4 b6-b5 De5-f5+ Rg6-h6 Cd4-e6 f4-f3 Df5-g5+ Rh6-h7 Dg5-g7+

[Uri Blass]

Not always forward backward solve the positions faster and there are cases when without forward backward the engine can find a different better move that without it you do not analyze it for enough time.

Could you show any example?

Not so easy of course to measure time of Forward- Backward, what I meant was interactive one of a somewhat experienced user.

But also as for stand-alone pondering started with empty hash: as for positions of long DsTM, there's much difference in time to "solution" with SMP-trials of course too, and if you want to test single threaded only, I'd advise for Forward- Backward here even more, if you want to find shortest DTM in reasonable time.
Or you just take engines that aren't made for game playing like Chest or Gustav too, working single threaded only at all, but these are somewhat uncomparable then at all, as well as it's also the point as for engines with option of DTM- search to be checked or unchecked.

As the saying goes: no rule without exception regards

I think that in many cases going backward and forward is slower for me relative to leaving one engine for a lot of time but maybe I do not know how to do it correctly.

if I go forward and wait for mate and start to go backward then often I may miss the right move when I go forward.
Even if I go forward very slowly and go backward I often find that the line is not the best line and I need again to go forward.

Usually what I do after a long time is simply waiting for a long time for the engine to find a mate and then going forward in the main line to see if I can improve it and going backward but the problem is that the engine later may forget mates that it had in the hash.

Note that in many cases I did not verify the written mate and trusted the analysis and I would like to have some fast option to verify that the mate is correct that should be faster relative to finding mates.

[peter]

I think that in many cases going backward and forward is slower for me relative to leaving one engine for a lot of time but maybe I do not know how to do it correctly.

if I go forward and wait for mate and start to go backward then often I may miss the right move when I go forward.
Even if I go forward very slowly and go backward I often find that the line is not the best line and I need again to go forward.

You need not go forward slowly but backward always only as quickly as any DTM is kept in output. If it gets lost, wait or go forward one plie again and wait there again, go on backward not until DTM is stable in output again. Normally you can go on backward with number of iterations in first one of output- iteration- countings as high as DTM from position reached is.

Better moves are found that way instead of the ones pasted before with longer output- line, if they aren't, but you think there could be some, try MultiPV or next best move now and then way backward.

As said, it's a matter of experience at all, but if you get used to it, you'll see, there (almost) isn't any shorter time of finding better moves along the lines and getting shortest DsTM, not with any engine capable of "hash- learning". That's so with as well as all A-B-searchers, pity (almost at all, compared with A-B) not with engines like LC0.

Another one thing I don't see very useful as for "such" DTM- puzzles: most of them aren't single best move positions at all, if you define that as moves relevantly better then alternative candidates, let's call them game changers. If there is one best move with DTM 20 and next best is 30, so what?

You can't judge engine's playing strength not even as for practically relevant mate search in game play because they (now and then at single SMP- trials) get the better for one DTM- output some minutes sooner or later then the other one game playing engine does.

"Such" positions are only good for comparing specialised mate search of its own and there engines like Huntsman prevail of course, not to speak about Chest and Gustav. SlowChess is a single one exception of this "rule" to me. Most of the other engines for game playing and specialised mate search have UCI options for it, e.g. Minic'sFindMate is rather good too, but of course there are many of the SF branches with certain puzzle- options (King Safety, Nullmove...) HekaStockfish from Michael Novak e.g. seems important to mention to me too, having FindMate option too togehter with many other parameters, some are useful for certain positions in mate search accordingly.

Just my two cents, yet thanks again for collecting and showing these positions, it's fun giving the one and the other one setting of interest a try with them now and then too of course

[Chessqueen]

next 2 positions in the suite

2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1 bm Rc1 dm 24
8/1R6/3pk3/p7/8/R7/P7/1KB2q2 w - - 0 1 bm Re3+ dm 38

analysis with slowchess after going forward and backward not from clear hash

FEN: 2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1

Slow64-avx2 [001]:

39/48 00:02 16,334k 6,980k +M24 Rc2-c1 Ba1-b2 Rc1-d1 Nf6-e8 Rd1-d3 Ne8-f6 Rd3xd6 Nf6-g8 Bc8-d7 Ng8-e7+ Kf5-e6 Ne7-g8 c4-c5 Bb2-c3 Ke6-f7 Bc3-a5 Rd6-g6 Ng8-h6+ Rg6xh6+ Kh4-g5 Rh6-f6 Ba5-d8 c5-c6 Bd8-c7 Kf7-e6 Bc7-b8 Rf6-f7 Kg5-g4 Ke6-d5+ Kg4-g5 Kd5-e4 Kg5-g6 Bd7-e6 Bb8-h2 c6-c7 Bh2xc7 Rf7xc7 Kg6-g5 Ke4-e5 Kg5-g6 Rc7-c3 Kg6-g7 Ke5-f5 Kg7-h6 Kf5-f6 Kh6-h7 Rc3-h3+

Uri which version of Slowchess are you using and how many cores ?

I use slowchessblitz2.9 with 7 cores.

I also used Slowchess 2.9 with 7 cores without going forward and backward and it took 28 moves to solve it
[fen]2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1 [/fen]
FEN: 2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1

Slow64-avx2:
2/1 00:00 273 0 +5.56 Rc2-c1 Ba1-b2
3/5 00:00 1k 0 +5.44 Rc2-c1 Ba1-b2 Rc1-g1
4/5+ 00:00 2k 0 +6.27 Rc2-c1
4/5+ 00:00 2k 0 +7.93 Rc2-c1
4/5+ 00:00 3k 0 +M28 Rc2-c1
4/9 00:00 4k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4
5/9 00:00 5k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4
6/13 00:00 6k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5
7/15 00:00 8k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7
8/16 00:00 10k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3
9/17 00:00 12k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6
10/19 00:00 14k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6
11/19 00:00 17k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5
12/20 00:00 21k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5
13/23 00:00 24k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q
14/28 00:00 29k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6
15/31 00:00 34k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5
16/33 00:00 39k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+
17/35 00:00 44k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4
18/37 00:00 51k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+
19/39 00:00 58k 0 +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+
20/43 00:00 65k 6,506k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5
21/45 00:00 73k 7,268k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6
22/45 00:00 82k 8,155k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+
23/49 00:00 90k 9,027k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7
24/49 00:00 100k 9,992k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+
25/49 00:00 112k 11,162k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+
26/51 00:00 441k 5,517k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6
27/53 00:00 447k 5,591k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
28/55 00:00 453k 5,036k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
29/55 00:00 459k 5,104k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
30/55 00:00 466k 5,178k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
31/55 00:00 480k 5,331k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
32/55 00:00 489k 5,438k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
33/55 00:00 499k 5,541k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
34/55 00:00 507k 5,069k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
35/55 00:00 515k 5,149k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
36/55 00:00 524k 5,239k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
37/55 00:00 995k 4,523k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
38/56 00:00 1,046k 4,549k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
39/56 00:02 13,022k 4,460k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
40/57 00:08 38,129k 4,656k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
41/57 00:08 41,574k 4,677k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
42/57 00:11 54,308k 4,698k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
43/57 01:36 450,167k 4,662k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
44/63 03:26 968,091k 4,696k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
45/63 03:39 1,032,404k 4,711k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
46/63 05:18 1,495,831k 4,692k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
47/63 06:53 1,927,072k 4,655k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
48/65 12:26 3,603,296k 4,826k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
49/65 13:28 3,919,480k 4,846k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
50/69 17:24 5,135,042k 4,917k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
51/69 18:52 5,594,424k 4,939k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
52/69 25:12 7,506,248k 4,962k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
53/69 28:51 8,579,672k 4,955k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+
54/69 36:10 10,828,421k 4,990k +M28 Rc2-c1 Ba1-d4 Rc1-h1+ Kh4-g3 Rh1-d1 Bd4-b2 Rd1-d3+ Kg3-h4 Kf5-g6 Nf6-g4 Bc8xg4 Kh4xg4 Rd3xd6 Kg4-f4 c4-c5 Kf4-e5 Rd6-d7 Bb2-c3 c5-c6 Ke5-e6 Rd7-d5 Ke6xd5 c6-c7 Kd5-e5 c7-c8Q Bc3-d4 Qc8-f5+ Ke5-d6 Qf5-b5 Kd6-e6 Qb5-e8+ Ke6-d6 Kg6-f5 Kd6-d5 Qe8-d7+ Kd5-c5 Kf5-e4 Bd4-b2 Qd7-c8+ Kc5-d6 Qc8-b8+ Kd6-c5 Qb8xb2 Kc5-d6 Qb2-b5 Kd6-e6 Qb5-c6+ Ke6-e7 Ke4-f5 Ke7-f7 Qc6-d7+ Kf7-f8 Kf5-f6 Kf8-g8 Qd7-g7+

[Paloma]

7R/2k1p2P/r2rP3/8/3p1R2/8/2P2p2/2K5 w - - 0 1 bm Rc8 dm 26
r7/4pk2/PP1r4/2R2P2/8/1KP5/8/R7 w - - 0 1 bm Rb5 dm 14
4r1k1/r7/2P1n1P1/1P1B1R2/P2b4/K7/3B4/7R w - - 0 1 bm b6 dm 13
8/6R1/3P4/4Q1p1/2p1P3/3rkP1P/6PK/4q3 w - - 0 1 bm Qc5+ dm 24
r6k/5p1P/1n3Np1/3P2P1/2n1PK2/1R6/p7/2R5 w - - 0 1 bm Ra1 dm 18
8/4n3/2p5/1k6/p1p1B2R/8/PB2n3/1K6 w - - 0 1 bm Be5 dm 22
1r2k3/2qb1p2/p3pBr1/4P1Pp/2P5/3Q4/1P1RBPP1/1K6 w - - 0 1 bm Bxh5 dm 20
8/3b4/kp4r1/3P4/p1P1p2R/4N3/1R5K/8 w - - 0 1 bm Rh7 dm 20
4r3/2P1rk2/4p1p1/2K1Qp1p/3P3P/2P2P2/6P1/8 w - - 0 1 bm d5 dm 23
8/8/2n5/7P/3K4/k1pB4/3b4/1R6 w - - 0 1 bm Kd5 dm 25
2r5/p4k2/6p1/1KP3Pp/1PR4P/4R3/8/6r1 w - - 0 1 bm c6 dm 23
2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1 bm Rc1 dm 24
8/1R6/3pk3/p7/8/R7/P7/1KB2q2 w - - 0 1 bm Re3+ dm 38
8/4kp1p/6p1/6P1/5R1P/2B4r/2K5/8 w - - 0 1 bm Kb3 dm 34
r3n3/P4r1p/3R2nk/2B1p3/2P1PpBP/5P2/8/R6K w - - 0 1 bm Rc6 dm 20
2n5/2r1b3/2k5/P7/1p6/1K1QB3/1P6/8 w - - 7 1 bm Ka4 dm 24

analysis of last problem by slowchess
...

Nr.5 is not the origin Pos. you gave in this Link on page 1:

You are right I meant position when white played 71.Ra1 because later at least one engine saw the mate but it seems that I forgot to replace the position and the position I gave is after 71.Ra1 Kh8
https://tcec-chess.com/#div=p&game=12&season=23

At move 72 stockfish red already saw the mate and initially I did not pay attention to it.

Because before 71.Ra1 the bK was on g7, not h8
false: r6k/5p1P/1n3Np1/3P2P1/2n1PK2/1R6/p7/2R5 w - - 0 1 bm Ra1
right: r7/5pkP/1n3Np1/3P2P1/2n1PK2/1R6/p7/2R5 w - - 0 1 bm Ra1

don't know wether is it dm 18 now
.

[Uri Blass]

Next result mate in at most 21 moves

FEN: 4r3/1n3k2/5B2/5K2/4R3/8/1P5P/8 w - - 0 1

Slow64-avx2 [001]:
2/2 00:00 111 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8
3/5 00:00 1k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4
4/8 00:00 2k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5
5/9 00:00 3k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6
6/11 00:00 3k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7
7/13 00:00 4k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8
8/16 00:00 6k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7
9/17 00:00 7k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7
10/21 00:00 9k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q
11/23 00:00 11k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5
12/25 00:00 13k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4
13/27 00:00 15k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4
14/28 00:00 19k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+
15/29 00:00 22k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4
16/31 00:00 26k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+
17/33 00:00 33k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5
18/35 00:00 40k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7
19/35 00:00 50k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+
20/37 00:00 53k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7
21/41 00:00 62k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
22/41 00:00 73k 0 +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
23/41 00:00 93k 9,260k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
24/41 00:00 101k 10,142k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
25/41 00:00 111k 11,111k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
26/44 00:00 131k 13,100k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
27/44 00:00 156k 7,792k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
28/44 00:00 248k 4,970k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
29/44 00:00 256k 5,118k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
30/44 00:00 275k 4,587k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
31/44 00:00 303k 4,334k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
32/44 00:00 352k 4,397k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
33/44 00:00 399k 4,438k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
34/44 00:00 622k 4,440k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
35/44 00:00 968k 4,840k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
36/45 00:00 1,007k 4,796k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
37/45 00:00 1,155k 4,813k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
38/46 00:00 1,335k 4,946k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
39/46 00:00 1,515k 5,050k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
40/46 00:00 1,641k 5,129k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
41/46 00:00 1,927k 5,354k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
42/47 00:03 24,162k 6,211k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
43/47 00:03 24,278k 6,209k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
44/55 00:04 25,649k 6,180k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
45/55 00:04 25,866k 6,188k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
46/55 00:05 35,701k 6,468k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
47/55 00:05 36,294k 6,481k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
48/55 00:10 71,558k 7,106k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+
49/59 00:33 260,368k 7,692k +M21 Re4xe8 Nb7-d6+ Kf5-g5 Kf7xe8 Kg5-g6 Nd6-e4 h2-h4 Ne4-c5 h4-h5 Nc5-e6 h5-h6 Ne6-f8+ Kg6-g7 Nf8-e6+ Kg7-g8 Ne6-f8 b2-b3 Nf8-d7 Bf6-g7 Nd7-b8 h6-h7 Nb8-c6 h7-h8Q Ke8-d7 Qh8-h5 Kd7-c7 b3-b4 Nc6xb4 Qh5-a5+ Kc7-c6 Qa5xb4 Kc6-c7 Bg7-e5+ Kc7-c6 Qb4-a5 Kc6-b7 Qa5-b5+ Kb7-a7 Be5-c7 Ka7-a8 Qb5-b8+

[Uri Blass]

update of positions
hope no mistakes now(of course some mates may be shorter).

7R/2k1p2P/r2rP3/8/3p1R2/8/2P2p2/2K5 w - - 0 1 bm Rc8 dm 26
r7/4pk2/PP1r4/2R2P2/8/1KP5/8/R7 w - - 0 1 bm Rb5 dm 14
4r1k1/r7/2P1n1P1/1P1B1R2/P2b4/K7/3B4/7R w - - 0 1 bm b6 dm 13
8/6R1/3P4/4Q1p1/2p1P3/3rkP1P/6PK/4q3 w - - 0 1 bm Qc5+ dm 24
r7/5pkP/1n3Np1/3P2P1/2n1PK2/1R6/p7/2R5 w - - 0 1 bm Ra1 dm 18
8/4n3/2p5/1k6/p1p1B2R/8/PB2n3/1K6 w - - 0 1 bm Be5 dm 22
1r2k3/2qb1p2/p3pBr1/4P1Pp/2P5/3Q4/1P1RBPP1/1K6 w - - 0 1 bm Bxh5 dm 20
8/3b4/kp4r1/3P4/p1P1p2R/4N3/1R5K/8 w - - 0 1 bm Rh7 dm 20
4r3/2P1rk2/4p1p1/2K1Qp1p/3P3P/2P2P2/6P1/8 w - - 0 1 bm d5 dm 23
8/8/2n5/7P/3K4/k1pB4/3b4/1R6 w - - 0 1 bm Kd5 dm 25
2r5/p4k2/6p1/1KP3Pp/1PR4P/4R3/8/6r1 w - - 0 1 bm c6 dm 23
2B5/8/3p1n2/5K2/2P4k/8/2R5/b7 w - - 0 1 bm Rc1 dm 24
8/1R6/3pk3/p7/8/R7/P7/1KB2q2 w - - 0 1 bm Re3+ dm 38
8/4kp1p/6p1/6P1/5R1P/2B4r/2K5/8 w - - 0 1 bm Kb3 dm 34
r3n3/P4r1p/3R2nk/2B1p3/2P1PpBP/5P2/8/R6K w - - 0 1 bm Rc6 dm 20
2n5/2r1b3/2k5/P7/1p6/1K1QB3/1P6/8 w - - 7 1 bm Ka4 dm 24
4r3/1n3k2/5B2/5K2/4R3/8/1P5P/8 w - - 0 1 bm Rxe8 dm 21
main line Rxe8 Nd6+ Kg5 Kxe8 and now mate in 19 based on tablebases.