Mate in 7 not so easy

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Ajedrecista
Posts: 1950
Joined: Wed Jul 13, 2011 9:04 pm
Location: Madrid, Spain.

Re: Mate in 7 not so easy.

Post by Ajedrecista »

Hello Vincent:
Vinvin wrote: ↑Wed Jul 20, 2022 3:52 am From the page http://outskirts.altervista.org/forum/v ... =42&t=2520

+M7 1.d4 bxa6 2.d5 cxd5 3.Ba4 a2 4.Nc3 Bxc3 5.Bd7 a1Q 6.Bg4 Bxd2 7.Re6+

[d]4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1
I tried the old engines that came in the Arena 2.0.1 GUI download:

Code: Select all

AnMon 5.60         (date of the executable: 2006/01/28).
Dragon 4.6         (date of the executable: 2004/10/20).
Hermann 2.4 64-bit (date of the executable: 2008/11/12).
Nejmet 3.07        (date of the executable: 2003/06/23).
ProDeo 1.5         (date of the executable: 2007/06/06).
Ruffian 1.05       (date of the executable: 2003/03/19).
Rybka 2.2 64-bit   (date of the executable: 2006/12/02).
SOS 5.1 for Arena  (date of the executable: 2005/02/22).
Spike 1.2          (date of the executable: 2006/05/24).
------------

Conditions:

· Intel Core i5-650 (3.2 GHz).
· Time limit: 30 minutes.
· Hash: 256 MB.
· Multi-PV = 1.
· 64-bit engines if available.
· Threads: 1 (for being deterministic).

------------

Summary of performances:

Code: Select all

Solving time: the lowest time (in seconds) to find a checkmate in 7.
N/A if a checkmate in 7 was not found within 30 minutes.
Better score of N/A if a checkmate was found within 30 minutes (best #8, then #9 and so on; if tied, the faster time to find that suboptimal checkmate).

==============================================
Solving time (SSSS.sss)     Engine
==============================================
         85.000             Nejmet 3.07
        184.260             Ruffian 1.05
        374.243             Spike 1.2
        427.253             AnMon 5.60
        583.434             Hermann 2.4 64-bit
          N/A               Rybka 2.2 64-bit
          N/A               Dragon 4.6
          N/A               ProDeo 1.5
          N/A               SOS 5.1 for Arena
------------

AnMon 5.60 was able to find the checkmate in 7:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1

AnMon 5.60:
   1-	00:00	           4	0	+5,51	Na6xb4 c5xb4
   1	00:00	           6	0	+5,51	Na6xb4 c5xb4
   1+	00:00	          10	0	+6,71	Re8f8+ Kf6e5
   1	00:00	          38	0	+7,05	Re8f8+ Kf6e5
   2	00:00	         185	0	+7,05	Re8f8+ Kf6e5
   3	00:00	         978	0	+7,27	Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6
   4	00:00	       3.986	0	+7,27	Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6
   4+	00:00	       5.872	0	+7,28	Na6b8 Kf6f5 d3d4+ Kf5g4 d2xe3 c5xd4 e3xd4 Kg4xh4
   4	00:00	       7.201	0	+8,00	Na6b8 Kf6f5 d2xe3 a3a2 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5
   5	00:00	      17.155	0	+8,26	Na6b8 Kf6f5 d2xe3 Kf5g4 Nd1f2+ Kg4xh5 e3xf4 Kh5xh4
   6	00:00	      64.898	0	+8,23	Na6b8 Kf6f5 d2xe3 Kf5g4 Nd1f2+ Kg4xh4 e3xf4 Kh4xh5
   6+	00:00	     166.033	0	+8,24	Na6c7 Kf6f5 d2xe3 Kf5f6
   6	00:00	     181.867	0	+8,69	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 a3a2 Re8a8
   7	00:00	     293.803	0	+8,73	Na6c7 Kf6f5 Kg8f8 Kf5g4 Re8a8 a3a2 Nd1c3 a2a1Q Ra8xa1 Kg4xh5
   8	00:01	   1.424.252	634.341	+8,63	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8f7 Kh4xh5
   8+	00:01	   1.876.303	634.341	+8,64	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 b4b3 Bc2xb3 d6d5 Ra8f8+ Kf6e7 Rf8f7+ Ke7e8 Bb3xa2
   8	00:01	   2.029.976	634.341	+9,02	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8h7 Kf5g4 Re8e6 Kg4xh5 Re6xh6+ Kh5g4 Nd1f2+ Kg4f5 Rh6h5+ Kf5e6 e3xf4
   9	00:03	   5.306.822	1.363.555	+9,42	Na6xb4 c5xb4 Re8f8+ Kf6e5 d3d4+ Ke5xd4 d2xe3+ Kd4e5 Rf8e8+ Ke5d5 e3xf4 Kd5c5 Re8a8 a3a2 Ra8xa2
  10+	00:12	  16.826.101	1.381.510	+9,43	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 Ke6d6 Rf8f6+ Kd6d7 Rf6f7+ Kd7d8
  10	00:12	  17.799.339	1.381.510	+9,86	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8a8 f4xe3 Nd1xe3+ Kf5e5 Ra8e8+ Ke5d4 Ne3d1 a3a2 Re8e4+ Kd4d5 Bc2b3+ Kd5c5 Bb3xa2 Kc5b5
  11+	00:29	  41.067.379	1.384.807	+9,87	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ Ke6d7 e3xf4 Kd7c7 Kg8g7 d6d5 Rf8f7+ Kc7d6 Rf7f6+ Kd6d7 Rf6f7+ Kd7e6 Rf7f6+ Ke6e7
  11	00:50	  72.435.246	1.404.097	+10,12	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4
  11+	02:13	 191.123.808	1.429.516	+10,13	d3d4 b7xa6 d4d5 Bb4xd2 d5xc6 a3a2 Nd1xe3 a2a1R c6c7 Ra1g1+ Kg8h7 Rg1g7+ Kh7xh6 Rg7g6+ Bc2xg6
  11+	02:14	 192.129.754	1.212.800	+11,95	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1R c7c8Q f4f3 e2xf3 d6d5 Kg8h8 d5d4 Kh8h7 Ra1a3 Kh7xh6 Ra3c3
  11+	02:15	 193.511.166	1.212.800	+12,15	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1R c7c8Q f4f3 e2xf3 d6d5 Kg8h8 a6a5 Kh8h7 Kf6f7 Kh7xh6 d5d4
  11+	02:16	 194.500.273	1.172.869	+13,43	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1R c7c8Q f4f3 e2xf3 Bb4a5 Kg8h8 Ba5c3 Nd1xc3 Ra1a3
  11+	02:20	 199.701.293	1.436.895	+13,61	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1R c7c8Q f4f3 e2xf3 Ra1a2 Kg8h8 Bb4c3 Nd1xc3 Kf6f7 Bc2b3+
  11+	02:21	 200.623.799	1.436.895	+15,47	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1R c7c8Q Bb4c3 Nd1xc3 Ra1g1+ Kg8h7 Rg1g4 Qc8xg4
  11+	02:22	 201.565.859	930.509	+18,65	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1B c7c8Q c5c4 Qc8xc4 d6d5 Qc4xd5 Bb4a3 Kg8h8 Ba3f8 Re8xf8+ Kf6e7+ Kh8g8 a6a5 Qd5f7+ Ke7d6 Qf7xf4+ Kd6c6
  11+	02:22	 201.840.454	930.509	+M16	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1N c7c8Q Bb4a3 Bc2b1 c5c4 Qc8xc4 Ba3b4 Bb1c2 Bb4c5 Nd1e3 d6d5 Qc4xd5 Bc5e7 Qd5f7+ Kf6e5 Qf7xe7+ Ke5d4 Qe7d6+ Kd4c3 Qd6e5+ Kc3b4 Re8b8+ Kb4a3 Qe5xa1+
  11+	02:22	 201.840.634	930.509	+M14	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1N c7c8Q c5c4 Qc8xc4 Bb4c5 Nd1e3 d6d5 Qc4xd5 Bc5e7 Qd5f7+ Kf6e5 Qf7xe7+ Ke5d4 Qe7d6+ Kd4c3 Qd6e5+ Kc3b4 Re8b8+ Kb4a3 Qe5xa1+
  11+	02:22	 201.851.382	930.509	+M13	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Bb4c3 Nd1xc3 Qa2e6 Re8xe6+ Kf6f7 Re6xd6 d2d1R Qc8d7+ Kf7f8 Qd7d8+ Kf8f7 Qd8f6+ Kf7e8 Bc2g6+
  11	02:22	 202.073.877	930.509	+M12	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Bb4c3 Nd1xc3 Qa2e6 Re8xe6+ Kf6f7 Re6xd6 d2d1R Qc8d7+ Kf7f8 Qd7d8+ Kf8f7 Qd8f6+ Kf7e8 Bc2g6+
  12+	02:51	 245.391.391	1.497.816	+M11	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Bb4c3 Nd1xc3 Qa2e6 Re8xe6+ Kf6f7 Re6xd6 d2d1R Qc8d7+ Kf7f8 Qd7d8+ Kf8f7 Qd8f6+ Kf7e8 Bc2g6+
  12+	02:51	 245.480.363	1.497.816	+M10	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Qa2xc2 Nd1f2 Qc2c1 Nf2e4+ Kf6f7 Ne4xd6+ Kf7f6 Qc8d7 Qc1b1 Re8f8+ Kf6e5 Nd6c4+ Ke5e4 Rf8e8+
  12	03:04	 266.412.645	1.628.565	+M10	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Qa2xc2 Nd1f2 Qc2c1 Nf2e4+ Kf6f7 Ne4xd6+ Kf7f6 Qc8d7 Qc1b1 Re8f8+ Kf6e5 Nd6c4+ Ke5e4 Rf8e8+
  13+	06:26	 630.758.993	1.628.250	+M9	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Qa2xc2 Nd1f2 Qc2c1 Nf2e4+ Kf6f7 Ne4xd6+ Kf7f6 Qc8d7 Qc1b1 Re8f8+ Kf6e5 Nd6c4+ Ke5e4 Rf8e8+
  13+	06:26	 630.913.547	1.478.349	+M8	d3d4 b7xa6 d4d5 e3xd2 d5xc6 a3a2 c6c7 a2a1Q c7c8Q Qa1a2+ Kg8h8 Qa2d5 Qc8d8+ Kf6f7 Qd8d7+ Kf7f6 Qd7e7+
  13+	06:26	 631.628.909	1.478.349	+M7	d3d4 b7xa6 d4d5 e3xd2 d5xc6 d6d5 c6c7 a3a2 c7c8Q Bb4a3 Kg8h8 Kf6f7 Kh8h7 d5d4 Qc8e6+
  13	06:26	 631.633.573	1.478.349	+M7	d3d4 b7xa6 d4d5 e3xd2 d5xc6 d6d5 c6c7 a3a2 c7c8Q Bb4a3 Kg8h8 Kf6f7 Kh8h7 d5d4 Qc8e6+
------------

Dragon 4.6 was unable to find the checkmate in 7 within 30 minutes although it was analyzing d4 for more than 20 minutes at depth 14. (Last output of the engine around 4:37).

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Dragon 4.6:
ucinewgame
RAZ infos
Temps restant : 0 secondes Temps limite : 1000000 secondes Temps limite absolu : 1000000 secondes
  10+	00:02	   4.239.575	0	+9,12	Na6xb4 c5xb4 d2xe3 d6d5 Re8f8+ Kf6e6 e3xf4 b7b5 f4f5+ Ke6e5 f5f6 a3a2 Rf8a8 a2a1N
  10	00:02	   4.331.748	2.119.787	+9,12	Na6xb4 c5xb4 Re8f8+ Kf6e5 Rf8e8+ Ke5d4 Nd1c3
  11	00:10	  22.638.162	2.165.874	+9,39	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Rf4xb4 b7b5 Rb4b3 Kh5xh4 Rb3xa3 b5b4
  12	00:28	  63.728.321	2.263.816	+9,39	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Rf4xb4 b7b5 Rb4b3 a3a2 Rb3a3 b5b4 Ra3xa2 Kh5xh4
  13+	01:04	 148.068.002	2.276.011	+9,79	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8e4 Kf5g4 Re4xb4 a3a2 Rb4xf4+ Kg4xh5 Rf4a4 b7b5 Ra4xa2 Kh5xh4 Ra2a6 Kh4h5
  13	01:26	 198.915.310	2.277.969	+9,84	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8e4 Kf5g4 Re4xb4 b7b5 Rb4xf4+ Kg4xh5 Bc2b3 d6d5 e3e4 c6c5 e4xd5 b5b4
  14+	03:20	 465.322.288	2.312.968	+10,24	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Kg8h7 a3a2 d3d4 a2a1R Bc2b3 Ra1b1 Bb3e6 Rb1b2 Nd1xb2 b7b5
  14	04:37	 647.319.818	2.326.611	+10,31	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ Ke6d7 e3xf4 b7b5 f4f5
------------

Hermann 2.4 64-bit found a checkmate in 9 quickly and finally found the checkmate in 7:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Hermann 2.4 64 bit:
  1/10	00:00	         107	107.000	+8,97	Na6xb4 c5xb4 d2xe3
  9/23	00:00	     642.446	1.041.241	+9,93	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d5 Ng4xh6
 10/27	00:02	   2.564.721	1.057.617	+10,35	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Bc2b3 d6d5 Rf4xb4
 11/27	00:06	   6.531.190	1.067.188	+10,44	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 f4xe3 Ra8xa2 Kf6e5 Nd1xe3 Ke5f4 Ne3c4 d6d5
 12/30	00:16	  17.366.177	1.061.373	+10,49	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 f4xe3 Ra8xa2 Kf6e5 Bc2b3 d6d5 Kg8g7 Ke5d4 Kg7xh6
 12/33+	00:34	  35.908.510	1.061.691	+10,49	d3d4 c5xd4 Na6xb4 d6d5 d2xe3 d4xe3 Bc2g6 f4f3 e2xf3 e3e2
 12/33+	00:34	  36.194.705	1.061.615	+10,99	d3d4 c5xd4 Na6xb4 d6d5 d2xe3 d4d3 Nb4xd3 f4xe3
 12/33	00:42	  45.700.460	1.069.918	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
 13/33	00:53	  57.592.714	1.074.792	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
 14/33	01:46	 115.437.938	1.091.251	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
 15/34	03:59	 264.114.335	1.102.406	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
 16/36	09:43	 647.347.600	1.109.547	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4xd2 Ba4d7 Bd2e1 Bd7g4 Be1xh4 Re8e6+ Kf6g5 Re6g6+
------------

Nejmet 3.07 performed very well:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Nejmet 3.07:
  1/2	00:00	           2	2	+8,00	Nd1xe3
  1/2	00:00	          15	15	+4,24	Nd1xe3
  1/2	00:00	          17	17	+4,24	d2xe3
  1/2	00:00	          28	28	+5,90	d2xe3
  1/2	00:00	          38	38	+5,90	Na6xb4
  1/2	00:00	         107	107	+6,00	Na6xb4
  2/4	00:00	         137	137	+6,00	Na6xb4 c5xb4
  2/4	00:00	         316	316	+6,00	Re8f8+
  2/4	00:00	         502	502	+6,01	Re8f8+ Kf6e5 Na6xb4
  2/4	00:00	         798	798	+6,01	Re8f8+ Kf6e5 Na6xb4
  3/6	00:00	       1.367	1.367	+5,96	Re8f8+ Kf6e5 Na6xb4 e3xd2 Rf8e8+ Ke5f6 Re8f8+ Kf6e6
  3/6	00:00	       2.887	2.887	+5,96	Re8f8+ Kf6e5 Na6xb4 e3xd2 Rf8e8+ Ke5f6 Re8f8+ Kf6e6
  4/8	00:00	       5.711	5.711	+5,93	Re8f8+ Kf6e5 d3d4+ c5xd4 Na6xb4 e3xd2 Nb4d3+ Ke5e6
  4/8	00:00	      13.470	13.470	+5,93	Re8f8+ Kf6e5 d3d4+ c5xd4 Na6xb4 e3xd2 Nb4d3+ Ke5e6
  5/10	00:00	      25.660	25.660	+6,14	Re8f8+ Kf6e5 d2xe3 b7xa6 e3xf4+ Ke5d5 Nd1e3+ Kd5d4
  5/10	00:00	      45.664	45.664	+6,14	Na6c7
  5/10	00:00	      51.508	51.508	+6,17	Na6c7 Bb4a5 Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5
  5/10	00:00	      55.372	55.372	+6,17	Na6b8
  5/10	00:00	      58.362	58.362	+6,51	Na6b8 Kf6f5 d2xe3 Kf5g4 Kg8g7
  5/10	00:00	      63.146	63.146	+6,51	Na6b8 Kf6f5 d2xe3 Kf5g4 Kg8g7
  6/12	00:00	      82.238	82.238	+6,51	Na6b8
  6/12	00:00	     105.599	105.599	+5,42	Na6b8 Kf6f5 d2xe3 a3a2 Re8f8+ Kf5g4 Nd1f2+ Kg4xh5 Rf8f5+ Kh5g6
  6/12	00:00	     134.344	134.344	+5,42	Na6c7
  6/12	00:00	     184.743	184.743	+6,84	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xf4
  6/12	00:00	     214.189	214.189	+6,84	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xf4
  7/14	00:00	     269.726	269.726	+6,84	Na6c7
  7/14	00:00	     293.844	293.844	+6,51	Na6c7 Bb4a5 Re8f8+ Kf6e7 Rf8f7+ Ke7d8 Nc7e6+ Kd8c8 d2xe3 a3a2 Rf7f8+ Kc8d7
  7/14	00:00	     366.526	366.526	+6,51	Re8f8+
  7/14	00:00	     517.342	517.342	+6,78	Re8f8+ Kf6e6 Bc2b3+ d6d5 Na6xb4 e3xd2 Nb4c2 c5c4 Nc2d4+ Ke6d7 Rf8f7+ Kd7d6
  7/14	00:00	     526.331	526.331	+6,78	Na6xb4
  7/14	00:00	     540.215	540.215	+7,42	Na6xb4 c5xb4 d2xe3 f4f3 Re8f8+ Kf6e6 Bc2b3+ d6d5 e2xf3
  7/14	00:00	     576.223	576.223	+7,42	Na6xb4 c5xb4 d2xe3 f4f3 Re8f8+ Kf6e6 Bc2b3+ d6d5 e2xf3
  8/16	00:00	     636.615	636.615	+7,55	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Rf8xf4 c6c5 Nd1f2
  8/16	00:00	     931.774	931.774	+7,55	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Rf8xf4 c6c5 Nd1f2
  9/18	00:00	     989.615	989.615	+7,55	Na6xb4
  9/18	00:00	   1.086.725	1.086.725	+8,06	Na6xb4 c5xb4 d2xe3 d6d5 e3xf4 Kf6f5 Kg8h7 Kf5xf4 Kh7xh6
  9/18	00:01	   2.334.853	2.334.853	+8,06	Na6xb4 c5xb4 d2xe3 d6d5 e3xf4 Kf6f5 Kg8h7 Kf5xf4 Kh7xh6
 10/20	00:02	   2.699.337	1.349.668	+8,16	Na6xb4 c5xb4 d2xe3 b7b5 e3xf4 Kf6f5 Re8e4 Kf5f6 Re4d4 c6c5
 10/20	00:03	   4.409.943	1.469.981	+8,16	Na6xb4 c5xb4 d2xe3 b7b5 e3xf4 Kf6f5 Re8e4 Kf5f6 Re4d4 c6c5
 11/22	00:03	   4.778.067	1.592.689	+8,16	Na6xb4
 11/22	00:04	   5.817.903	1.454.475	+8,75	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 Rf8xf4 c6c5 e3e4 b7b5 e4xd5+ Ke6d6
 11/22	00:07	  10.925.080	1.560.725	+8,75	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 Rf8xf4 c6c5 e3e4 b7b5 e4xd5+ Ke6d6
 12/24	00:08	  11.613.765	1.451.720	+8,75	Na6xb4
 12/24	00:09	  13.859.002	1.539.889	+9,02	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Rf8xf4 c6c5 Bc2b3+ d6d5 Kg8h7 Ke6d6 Kh7xh6 b7b5
 12/24	00:19	  28.239.169	1.486.272	+9,02	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Rf8xf4 c6c5 Bc2b3+ d6d5 Kg8h7 Ke6d6 Kh7xh6 b7b5
 13/26	00:21	  30.852.151	1.469.150	+9,02	Na6xb4
 13/26	00:26	  36.999.153	1.479.966	+9,32	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8e4 Kf5g4 Re4xf4+ Kg4g3 Rf4xb4 b7b5 Rb4b3 Kg3xh4 Rb3xa3 Kh4xh5
 13/26	00:41	  58.701.476	1.431.743	+9,32	d3d4
 13/26	01:25	 124.207.096	1.461.259	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4xd2 Ba4d7 Bd2e1 Bd7g4 Be1xh4 Re8e6+ Kf6g5 Re6g6+
 13/26	01:46	 159.134.595	1.501.269	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4xd2 Ba4d7 Bd2e1 Bd7g4 Be1xh4 Re8e6+ Kf6g5 Re6g6+
 14/28	01:53	 170.878.821	1.512.201	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4xd2 Ba4d7 Bd2e1 Bd7g4 Be1xh4 Re8e6+ Kf6g5 Re6g6+
------------

ProDeo 1.5 was unable to find the checkmate in 7 within 30 minutes. (Last output of the engine around 10:41):

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

ProDeo 1.5:
   1	00:00	          30	30.000	+5,29	Na6xb4 c5xb4 d2xe3
   2	00:00	         312	312.000	+5,29	Na6xb4 c5xb4 d2xe3
   2	00:00	         409	409.000	+5,29	Re8f8+
   2	00:00	         312	312.000	+5,29	Na6xb4 c5xb4 d2xe3
   3	00:00	       3.658	3.658.000	+6,16	Na6xb4 c5xb4 d2xe3 f4xe3 Re8f8+ Kf6e5 Nd1xe3
   4	00:00	      11.668	11.668.000	+6,59	Na6xb4 c5xb4 Bc2b3 d6d5 d2xe3
   5	00:00	      33.882	33.882.000	+6,94	Na6xb4 c5xb4 Bc2b3 e3xd2 Nd1f2 Kf6f5 Re8f8+ Kf5e5 Nf2g4+ Ke5d4 Rf8xf4+ Kd4c3 Ng4xh6
   6	00:00	     108.844	108.844.000	+7,85	Na6xb4 c5xb4 d2xe3 d6d5 Bc2b3 b7b5 Re8f8+ Kf6e5 e3xf4+ Ke5d4
   7	00:00	     288.842	288.842.000	+7,90	Na6xb4 c5xb4 d2xe3 d6d5 Bc2b3 f4f3 Re8f8+ Kf6e6 e2xf3
   8	00:00	     631.655	631.655.000	+7,97	Na6xb4 c5xb4 d2xe3 d6d5 d3d4 b7b6 e3xf4 c6c5 Re8a8 c5xd4
   9	00:00	   1.790.784	1.790.784.000	+9,32	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Kg7xh6 Kf5f6 Re8a8 f4xe3 Nd1xe3
  10	00:01	   4.390.519	4.390.519	+10,01	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Kg7xh6 Kf5f6 e3xf4 b7b5 Bc2b3 Kf6f5
  11	00:04	  12.981.449	3.245.362	+10,01	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Kg7xh6 Kf5f6 e3xf4 b7b5 Bc2b3 d5d4 Re8e6+ Kf6f7
  12	00:16	  51.544.537	3.221.533	+10,44	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 b7b5 e3xf4 c6c5 Nd1e3 c5c4 d3xc4 b5xc4 Ne3xc4
  13	01:01	 189.623.055	3.160.384	+12,30	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 d6d5 d2xe3 b7b5 e3xf4 c6c5 Nd1e3+ Kf5xf4 Kg7xh6 c5c4
  14	01:42	 323.619.578	3.204.154	+12,30	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 d6d5 d2xe3 b7b5 e3xf4 c6c5 Nd1e3+ Kf5xf4
  15	06:04	1.157.154.157	3.178.994	+14,12	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 e3xd2 Kg7xh6 Kf5f6
  16	10:41	2.046.776.154	3.193.098	+14,48	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 b7b5 d2xe3 d6d5 e3e4+ Kf5g4 Kg7xh6 c6c5 Kh6g6
Fun fact: ProDeo 1.5 reaching more than 1790 MN/s on single core at depth 9 is a new record for me for raw speed in a chess engine. Disgracefully, it was not enough to find the checkmate.

------------

Ruffian 1.05 did not have any problems to find the checkmate in 7:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Ruffian 1.0.5:
  1/3	00:00	           4	0	+5,71	d2xe3 b7xa6 e3xf4
  1/3	00:00	           8	0	+6,60	Na6xb4 c5xb4 d2xe3
  1/6	00:00	         146	0	+6,99	Re8f8+ Kf6e7
  2/9	00:00	         742	0	+6,98	Re8f8+ Kf6e5 d3d4+ Ke5d5
  3/10	00:00	       3.033	0	+7,12	Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5
  4/13	00:00	       6.884	0	+7,34	Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6 Na6xb4 c5xb4 Re4xb4 e3xd2 Rb4xb7
  5/15	00:00	      29.224	2.922.400	+7,48	Re8f8+ Kf6e7 Rf8f7+ Ke7d8 Rf7xb7 a3a2 Rb7b8+ Kd8e7 Rb8b7+ Ke7e6
  6/18	00:00	     120.614	4.020.466	+7,60	Re8f8+ Kf6e6 Bc2b3+ Ke6e5 Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3
  7/21	00:00	     487.884	3.484.885	+7,72	Re8f8+ Kf6e5 d3d4+ Ke5e6 Na6xb4 c5xb4 d2xe3 f4xe3 Bc2b3+ d6d5 Nd1xe3
  7/21	00:00	     590.528	3.473.694	+8,62	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xf4 Re8f8+ Kf4g4 Rf8f6
  8/23	00:00	     779.274	3.388.147	+8,18	Na6c7 Kf6f5 d2xe3 Kf5g4 e3xf4 Bb4a5 Nc7e6 a3a2 Nd1e3+ Kg4xh4
  9/26	00:00	   1.734.253	3.272.175	+7,88	Na6c7 Kf6f5 d2xe3 Kf5g4 Re8a8 Kg4xh4 e3xf4 Kh4xh5 Kg8f7
  9/26	00:00	   2.088.040	3.367.806	+8,39	Re8f8+ Kf6e7 Na6xb4 c5xb4 Rf8f7+ Ke7d8 d2xe3 f4xe3 Rf7xb7 c6c5 Rb7a7 d6d5 Nd1xe3
  9/26	00:00	   2.630.840	3.330.177	+8,86	Na6xb4 c5xb4 d2xe3 d6d5 Re8f8+ Kf6e6 e3xf4 b7b6 f4f5+ Ke6e5 f5f6 a3a2 Rf8a8
 10/26	00:01	   3.527.731	3.392.049	+9,05	Na6xb4 c5xb4 d2xe3 b7b5 Bc2b3 d6d5 Re8c8 f4xe3 Rc8xc6+ Kf6e5 Kg8g7 Ke5d4 Kg7xh6
 11/29+	00:01	   5.988.794	3.422.168	+9,40	Na6xb4
 11/29	00:02	   7.640.031	3.472.741	+9,60	Na6xb4 c5xb4 d2xe3 d6d5 Re8f8+ Kf6e7 e3xf4 b7b6 Rf8f7+ Ke7d6 Kg8g7 c6c5 Rf7f6+ Kd6e7 Rf6xh6
 12/30	00:03	  12.940.063	3.545.222	+9,67	Na6xb4 c5xb4 d2xe3 d6d5 Re8f8+ Kf6e7 e3xf4 b7b5 f4f5 Ke7d6 Kg8g7 c6c5 Kg7xh6 a3a2 Rf8a8
 13/34+	00:06	  22.348.260	3.552.982	+10,02	Na6xb4
 13/34	00:12	  43.913.657	3.590.650	+10,30	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Rf4xb4 b7b5 Nd1c3 Kh5g6 Rb4b3 Kg6h5 Kg8g7 Kh5xh4 Rb3xa3
 14/37+	00:19	  71.860.701	3.596.631	+10,65	Na6xb4
 14/37	00:25	  91.962.534	3.614.879	+10,68	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4xh5 Rf4xb4 b7b5 Bc2b3 Kh5g6 Bb3f7+ Kg6f6 Rb4b3 b5b4 Rb3xb4 Kf6e5
 15/39+	00:44	 161.199.564	3.635.533	+11,03	Na6xb4
 15/39	01:19	 290.457.606	3.652.176	+11,48	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5g4 Rf8xf4+ Kg4g3 Rf4xb4 b7b5 Bc2b1 Kg3g2 Rb4b3 Kg2f1 Nd1c3 Kf1f2 e3e4 b5b4 Rb3xb4
 15/40	01:44	 382.678.123	3.649.419	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a6a5 Re8e6+
 16/40	01:49	 399.511.359	3.656.854	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a6a5 Re8e6+
 17/42	02:13	 492.634.374	3.696.791	+M10	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4a5 Ba4d7 Ba5d8 Re8e6+ Kf6f5 Re6xe3+ Kf5f6 Re3e6+ Kf6f5 Re6e8+ Kf5f6 Nd1f2 f4f3 Nf2g4+
 18/42	03:04	 695.202.895	3.772.945	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4a5 Nd1c3 Ba5xc3 Ba4d7 e3xd2 Bd7g4 d2d1Q Re8e6+
 19/42	03:09	 714.782.031	3.779.116	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 Bb4a5 Nd1c3 Ba5xc3 Ba4d7 e3xd2 Bd7g4 d2d1Q Re8e6+
------------

Rybka 2.2 64-bit found the same checkmate in 9 than Hermann 2.4 64-bit but got stuck there:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Rybka 2.2 64 bit:
   2	00:00	         637	20.384	+6,29	Re8f8+
   3	00:00	       2.186	69.952	+6,71	Re8f8+
   4	00:00	       4.441	94.741	+9,22	Re8f8+ Kf6e6
   5	00:00	       7.981	170.261	+9,22	Re8f8+ Kf6e7 Na6xb4
   6	00:00	      10.589	172.113	+9,91	Re8f8+ Kf6e7 Na6xb4 c5xb4 d2xe3
   7	00:00	      22.723	294.536	+9,91	Re8f8+ Kf6e6 Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 Ke6e5
   8	00:00	      40.362	375.733	+9,91	Re8f8+ Kf6e6 Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 Ke6e5 Ne3g4+
   8	00:00	      70.906	419.697	+10,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
   9	00:00	      90.341	422.416	+10,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  10	00:00	     141.317	420.664	+10,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  11	00:00	     283.568	441.968	+10,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  12	00:01	     582.747	454.480	+10,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  13	00:02	   1.326.147	474.816	+10,78	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  14	00:07	   3.621.063	491.251	+10,92	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  15	00:17	   8.229.080	494.749	+10,91	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+
  16	00:46	  22.113.957	485.343	+10,95	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 Re8e4 Kg4xh4 Re4xf4+ Kh4g3 Rf4xb4 b7b5 Kg8g7 Kg3h3
  17	01:51	  50.969.695	466.788	+11,60	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 Re8e4 Kg4xh4 Re4xf4+ Kh4g3 Rf4xb4 Kg3g2 Rb4xb7 Kg2f1
  18	04:40	 124.350.665	454.842	+11,60	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 Re8e4 Kg4xh4 Re4xf4+ Kh4g3 Rf4xb4 Kg3g2 Rb4xb7 Kg2f1
  19	11:32	 305.513.599	451.711	+11,60	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 Re8e4 Kg4xh4 Re4xf4+ Kh4g3 Rf4xb4 Kg3g2 Rb4xb7 Kg2f1
  19	14:42	 389.576.293	452.072	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  20	14:48	 395.801.906	456.074	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  21	14:57	 404.701.489	461.799	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  22	15:06	 414.865.421	468.550	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  23	15:16	 426.027.338	475.932	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  24	15:26	 437.806.339	483.780	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  25	15:37	 450.356.778	492.048	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  26	15:48	 463.335.747	500.414	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  27	15:59	 476.719.121	509.022	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  28	16:10	 490.586.799	517.772	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  29	16:21	 504.478.629	526.414	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  30	16:32	 519.187.818	535.454	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  31	16:44	 533.727.391	544.257	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  32	16:55	 548.692.938	553.166	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  33	17:07	 563.894.528	562.024	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  34	17:19	 579.237.551	570.892	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  35	17:31	 594.732.036	579.470	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  36	17:43	 611.058.549	588.474	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  37	17:55	 627.428.736	597.383	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  38	18:08	 644.270.853	606.398	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  39	18:20	 660.640.815	614.804	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  40	18:32	 677.150.898	623.134	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  41	18:45	 693.408.812	631.190	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  42	18:57	 710.587.281	639.613	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  43	19:11	 728.730.075	648.269	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  44	19:24	 746.368.288	656.563	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  45	19:37	 764.032.680	664.740	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  46	19:50	 782.094.340	673.021	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  47	20:03	 801.172.480	681.678	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  48	20:17	 820.674.482	690.331	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  49	20:30	 839.329.943	698.359	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  50	20:44	 859.014.885	706.645	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  51	20:58	 878.420.513	714.714	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  52	21:12	 898.376.569	722.838	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  53	21:26	 918.205.800	730.773	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  54	21:41	 938.801.625	738.909	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  55	21:56	 960.716.304	747.361	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  56	22:11	 982.390.779	755.700	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  57	22:25	1.002.709.035	763.347	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  58	22:39	1.023.041.103	770.696	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
  59	22:53	1.042.942.257	777.803	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2 Re8e6+
It seems that Rybka 2.2 64-bit reached a search depth limit (depth 59).

------------

SOS 5.1 for Arena was unable to find the checkmate in 7 within 30 minutes:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

SOS 5.1 for Arena:
  1/5	00:00	           6	0	+8,49	Na6xb4
  1/6	00:00	          13	0	+8,87	Na6xb4
  2/9	00:00	         105	0	+8,87	Na6xb4 c5xb4 d2xe3
  3/9	00:00	         241	0	+8,87	Na6xb4 c5xb4 d2xe3
  4/15	00:00	       2.043	0	+8,87	Re8f8+ Kf6e5 Rf8e8+ Ke5d5 Na6c7+
  5/18	00:00	       5.664	0	+8,80	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8
  6/18	00:00	       6.042	0	+8,80	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8
  6/18	00:00	       6.243	0	+8,91	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8
  6/18	00:00	       8.088	0	+9,57	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8
  7/21	00:00	      14.394	0	+9,57	Na6xb4 c5xb4 d2xe3 f4xe3 Bc2b3 c6c5 Nd1xe3
  7/21	00:00	      14.887	0	+9,69	Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 a3a2 Re8a8
  8/21	00:00	      32.955	0	+9,69	Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 a3a2 Re8a8
  8/21	00:00	      35.795	0	+9,80	Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 a3a2 Re8a8
  8/21	00:00	      47.098	0	+10,24	Na6xb4 c5xb4 d2xe3 f4xe3 Nd1xe3 a3a2 Re8a8
  9/21	00:00	      99.755	0	+10,28	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 e3xf4 c6c5 Bc2b3+ d6d5 e2e4
  9/21	00:00	     104.330	584.202	+10,39	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 e3xf4 c6c5 Bc2b3+ d6d5 e2e4
 10/25	00:00	     269.393	686.759	+10,49	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 e3xf4 c6c5 Bc2b3+ d6d5 e2e4
 10/26	00:00	     282.937	686.759	+10,61	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 e3xf4 c6c5 Bc2b3+ d6d5 e2e4
 10/26	00:00	     297.416	686.759	+10,72	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 c6c5 e2e4
 10/26	00:00	     340.304	686.759	+11,05	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 c6c5 e2e4
 11/26	00:00	     547.640	862.710	+11,05	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e5 d3d4+ Ke5e6 Bc2b3+ d6d5 e3xf4 b7b6 e2e4
 11/26	00:00	     569.768	862.710	+11,16	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e5 d3d4+ Ke5e6 Bc2b3+ d6d5 e3xf4 b7b6 e2e4
 12/28	00:01	   1.218.594	1.066.851	+11,26	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e5 e3xf4+ Ke5d4 Bc2b3 d6d5 e2e3+ Kd4xd3 Kg8g7
 12/28	00:01	   1.254.231	1.066.734	+11,37	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e5 e3xf4+ Ke5d4 Bc2b3 d6d5 e2e3+ Kd4xd3 Kg8g7
 13/32	00:02	   3.154.971	1.119.151	+11,43	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 b7b5 e2e4 Ke6d7 e4xd5 c6c5 Kg8f7
 13/32	00:02	   3.201.458	1.119.151	+11,54	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 b7b5 e2e4 Ke6d7 e4xd5 c6c5 Kg8f7
 13/32	00:02	   3.279.863	1.119.151	+11,76	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 b7b5 e2e4 Ke6d7 e4xd5 c6c5 Kg8f7
 13/32	00:02	   3.346.820	1.119.151	+11,87	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 b7b5 Nd1e3 Ke6d7 Ne3g4
 13/32	00:03	   3.416.205	1.133.527	+11,98	Na6xb4 c5xb4 d2xe3 Kf6f5 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 b7b5 Nd1e3 Ke6d7 Ne3g4
 13/32	00:03	   3.756.451	1.139.764	+12,09	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 c6c5 e3e4+ Kf5g4 Kg7xh6 Kg4xh4 Re8f8
 13/32	00:03	   4.055.301	1.139.764	+12,20	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 c6c5 e3e4+ Kf5g4 Kg7xh6 Kg4xh4 Bc2b3
 13/32	00:03	   4.222.770	1.145.041	+12,31	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 c6c5 e3e4+ Kf5g4 Kg7xh6 Kg4xh4 Bc2b3
 14/34	00:07	   8.325.432	1.184.047	+12,32	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 b7b6 Re8f8+ Kf5e6 Bc2b3+ d6d5 e3xf4 Ke6e7 Rf8f7+ Ke7e6 Rf7f6+ Ke6d7 Rf6xh6
 14/34	00:07	   9.057.614	1.189.456	+12,43	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 b7b6 Re8f8+ Kf5e6 e3xf4 Ke6e7 Rf8f7+ Ke7e8 Rf7a7 c6c5 Kg7xh6
 14/38	00:08	  10.263.953	1.192.096	+12,98	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 b7b6 Re8f8+ Kf5e6 e3xf4 Ke6e7 Rf8f7+ Ke7e8 Rf7a7 c6c5 Kg7xh6
 14/38	00:08	  10.656.837	1.193.019	+13,09	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 b7b6 d3d4+ Kf5g4 Kg7xh6 c6c5 e3xf4 c5xd4 f4f5
 15/38	00:14	  17.960.025	1.203.215	+13,18	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 c6c5 Ra8xa2 b7b5 Bc2b3 f4xe3 Nd1xe3 Kf6e5 Ne3g4+ Ke5d4 Ng4xh6
 16/39	00:29	  35.885.165	1.215.344	+13,28	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 f4xe3 Kg7xh6 Kf5f4 Ra8xa2 d6d5 Bc2b3 b7b5 d3d4
 16/39	00:30	  36.604.191	1.215.425	+13,39	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 f4xe3 Kg7xh6 Kf5f4 Ra8xa2 d6d5 Bc2b3 b7b5 d3d4
 17/39	01:04	  78.649.139	1.222.128	+13,46	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 c6c5 Bc2b3 b7b5 Bb3xa2 f4xe3 Nd1xe3 c5c4 d3xc4 b5xc4 Ba2xc4 Kf6e5 Kg8g7
 17/39	01:05	  80.039.889	1.222.839	+13,57	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 c6c5 Bc2b3 b7b5 Bb3xa2 f4xe3 Nd1xe3 c5c4 d3xc4 b5xc4 Ba2xc4 Kf6e5 Kg8f7
 17/42	01:27	 109.136.932	1.246.891	+13,65	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 e3xd2 Nd1f2 d2d1Q Bb3xd1 a3a2 d3d4 a2a1N e2e4+ f4xe3/ep Re8xe3 d6d5 Kg7f7
 18/43	03:00	 227.995.644	1.264.331	+13,67	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Nd1f2+ Kg4g3 Nf2e4+ Kg3xh4 Ne4xd2 d6d5 Kh6g6 d5d4 Nd2f3+ Kh4g3 Nf3xd4 c6c5 Nd4e6
 18/43	03:02	 230.464.436	1.263.814	+13,74	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Nd1f2+ Kg4g3 Nf2e4+ Kg3xh4 Ne4xd2 d6d5 Kh6g6 d5d4 Nd2f3+ Kh4g3 Nf3xd4 c6c5 Nd4e6
 18/43	03:05	 234.468.415	1.263.983	+13,80	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 d2xe3 Kg4xh5 e3xf4 Kh5xh4 f4f5 a3a2 Re8a8 a2a1Q+ Ra8xa1 Kh4g5 f5f6 Kg5f4 Kg7xh6
 18/43	03:13	 245.348.145	1.266.083	+14,40	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 d2xe3 Kg4xh5 e3xf4 Kh5xh4 f4f5 a3a2 Re8a8 a2a1Q+ Ra8xa1 Kh4g5 f5f6 Kg5f4 Kg7xh6
 19/44	06:15	 488.842.022	1.303.226	+14,40	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 d2xe3 f4f3 Re8e4+ Kg4g3 e2xf3 Kg3xf3 Re4xb4 c6c5 Rb4xb7 c5c4 d3xc4 Kf3e4 Kg7xh6
 19/44	06:19	 494.183.361	1.303.353	+14,41	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 d2xe3 f4f3 Re8e4+ Kg4g3 e2xf3 Kg3xf3 Re4xb4 c6c5 Rb4xb7 c5c4 d3xc4 Kf3e4 Kg7xh6
 19/44	06:30	 509.755.557	1.304.463	+14,56	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 d2xe3 f4f3 Re8e4+ Kg4g3 e2xf3 Kg3xf3 Re4xb4 c6c5 Rb4xb7 c5c4 d3xc4 Kf3e4 Kg7xh6
 19/44	06:39	 522.022.201	1.305.788	+14,59	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 Kh4xh5 Nd1f2 a3a2 Bb3xa2 Kh5h4 Re8e3 b7b5 Re3h3+
 19/44	06:42	 526.111.277	1.305.568	+14,71	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 Kh4xh5 Nd1f2 a3a2 Bb3xa2 Kh5h4 Re8e3 b7b5 Re3h3+
 20/47	19:12	1.572.103.437	1.364.126	+14,72	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3 b7b6 Bb3f7+ Kh5g4 Kg7xh6 Kg4g3 Bf7e6
 20/47	19:15	1.575.440.946	1.363.959	+14,73	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3 b7b6 Bb3f7+ Kh5g4 Kg7xh6 Kg4g3 Bf7e6
 20/47	19:18	1.580.505.048	1.363.849	+14,78	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3 b7b6 Bb3f7+ Kh5g4 Kg7xh6 Kg4g3 Bf7e6
 20/47	19:21	1.584.526.281	1.363.738	+14,89	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3 b7b6 Bb3f7+ Kh5g4 Kg7xh6 Kg4g3 d3d4
 20/47	19:32	1.599.635.074	1.363.784	+14,92	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3
 20/47	19:35	1.603.321.369	1.363.392	+14,93	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 e2e3
 20/47	19:38	1.606.693.957	1.363.186	+15,04	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 f4f5 c6c5 f5f6 b7b5 e2e3 c5c4
 20/47	19:40	1.609.400.868	1.363.115	+15,15	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 f4f5 c6c5 f5f6 b7b5 e2e3
 20/47	19:42	1.611.398.338	1.363.084	+15,26	Na6xb4 c5xb4 Bc2b3 Kf6f5 d2xe3 Kf5g4 e3xf4 Kg4xh4 Kg8g7 a3a2 Bb3xa2 b4b3 Ba2xb3 Kh4xh5 f4f5 c6c5 f5f6 b7b5 e2e3
 20/47	23:49	1.952.903.314	1.365.930	+15,31	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	23:52	1.955.936.765	1.365.675	+15,32	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	23:56	1.960.898.094	1.365.192	+15,43	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 Bb3xa2 Kh4g4 Ba2xd5
 20/47	23:59	1.964.904.802	1.364.900	+15,54	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 Bb3xa2 Kh4g4
 20/47	24:23	1.995.349.661	1.363.695	+15,64	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	24:24	1.997.145.465	1.363.489	+15,65	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	24:28	2.002.153.804	1.363.181	+15,76	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 b7b6 h7h8Q+ Kh4g3 Re8f8 a3a2 Bb3xd5 c6xd5 Rf8f7 a2a1N Qh8xa1
 20/47	24:31	2.005.094.518	1.363.087	+15,77	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 b7b6 h7h8Q+
 20/47	25:00	2.041.639.134	1.360.383	+15,80	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	25:03	2.044.452.520	1.360.097	+15,81	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 h7h8Q+ Kh4g4 Re8f8 a2a1R Qh8xa1 f4f3
 20/47	25:09	2.052.547.212	1.359.517	+15,93	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 h7h8Q+ Kh4g4 Re8f8 a2a1R Qh8xa1 f4f3
 20/47	27:14	2.070.857.380	1.360.756	+16,00	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	27:22	2.061.509.179	1.359.959	+16,01	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5
 20/47	27:24	2.058.489.335	1.359.782	+16,02	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 Bb3xa2 Kh4h3 Re8f8 Kh3g3
 20/47	27:26	2.056.709.896	1.359.657	+16,03	Na6xb4 c5xb4 Bc2b3 Kf6f5 Kg8g7 Kf5g4 Kg7xh6 e3xd2 Kh6g6 Kg4xh4 h5h6 d6d5 h6h7 a3a2 Bb3xa2 Kh4h3 Re8f8 Kh3g3 Ba2xd5 b4b3
There was an integer overflow around minute 26 of the search and nodes were counted backwards since then. The number of nodes of the last line should be 2^32 - 2,056,709,896 = 2,238,257,400.

------------

Spike 1.2 passed the test:

Code: Select all

FEN: 4R1K1/1p6/N1pp1k1p/2p4P/1b3p1P/p2Pp3/2BPP3/3N4 w - - 0 1 

Spike 1.2:
   0	00:00	           0	0	+6,84	
   1	00:00	         318	15.142	+8,16	d2xe3 b7xa6 e3xf4
   1	00:00	         390	18.571	+8,16	d2xe3 b7xa6 e3xf4
   2	00:00	         781	35.500	+8,09	d2xe3 a3a2 Re8f8+ Kf6e7 Rf8f7+ Ke7e6
   2	00:00	       1.340	60.909	+8,09	d2xe3 a3a2 Re8f8+ Kf6e7 Rf8f7+ Ke7e6
   3	00:00	       1.992	86.608	+8,16	d2xe3 b7xa6 e3xf4
   3	00:00	       3.704	154.333	+8,16	d2xe3 b7xa6 e3xf4
   4	00:00	       4.772	190.880	+7,74	d2xe3 b7xa6 Nd1f2 a3a2 Nf2g4+ Kf6f5 Ng4xh6+ Kf5f6
   4	00:00	      10.792	385.428	+8,00	Re8f8+ Kf6e7 Rf8f7+ Ke7d8 d2xe3 a3a2 Rf7f8+ Kd8d7 Rf8f7+ Kd7c8
   4	00:00	      13.861	462.033	+8,00	Re8f8+ Kf6e7 Rf8f7+ Ke7d8 d2xe3 a3a2 Rf7f8+ Kd8d7 Rf8f7+ Kd7c8
   5	00:00	      20.399	618.151	+8,09	Re8f8+ Kf6e7 Rf8f7+ Ke7d8 d2xe3 a3a2 Rf7f8+ Kd8d7 Rf8f7+ Kd7c8 Rf7c7+ Kc8d8
   5+	00:00	      27.878	696.950	+8,30	Na6c7 a3a2 d3d4
   5+	00:00	      27.878	696.950	+8,30	Na6c7 a3a2 d3d4
   5	00:00	      35.769	777.586	+8,86	Na6c7 Bb4a5 Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6 Re4xe3 Ba5xc7 Re3xa3
   5	00:00	      42.905	809.528	+8,86	Na6c7 Bb4a5 Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6 Re4xe3 Ba5xc7 Re3xa3
   6+	00:00	      44.296	820.296	+9,17	Na6c7 Bb4a5 Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6 Re4xe3 Ba5xc7 Re3xa3
   6+	00:00	      44.296	820.296	+9,17	Na6c7 Bb4a5 Re8f8+ Kf6e5 d3d4+ Ke5xd4 Rf8xf4+ Kd4e5 Rf4e4+ Ke5f6 Re4xe3 Ba5xc7 Re3xa3
   6	00:00	      52.928	867.672	+9,20	Na6c7 Bb4a5 Re8f8+ Kf6e7 Rf8f7+ Ke7d8 Nc7e6+ Kd8c8 d2xe3
   6	00:00	      67.610	979.855	+9,20	Na6c7 Bb4a5 Re8f8+ Kf6e7 Rf8f7+ Ke7d8 Nc7e6+ Kd8c8 d2xe3
   7	00:00	      87.426	1.053.325	+8,93	Na6c7 Bb4a5 Re8e6+ Kf6f5 Re6g6 Kf5e5 d3d4+ Ke5xd4 Rg6xd6+ Kd4c4 d2d3+ Kc4b4
   7+	00:00	     107.065	1.127.000	+9,50	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 f4xe3 Nd1xe3
   7+	00:00	     107.065	1.127.000	+9,50	Na6xb4 c5xb4 d2xe3 a3a2 Re8a8 f4xe3 Nd1xe3
   7	00:00	     150.861	1.300.525	+9,58	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d5 Ng4xh6
   7	00:00	     165.158	1.331.919	+9,58	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d5 Ng4xh6
   8	00:00	     276.129	1.551.286	+9,82	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d4 Ng4xh6
   8	00:00	     339.416	1.631.807	+9,82	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d4 Ng4xh6
   9+	00:00	     358.187	1.643.059	+10,12	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d4 Rf3f4+
   9+	00:00	     358.187	1.643.059	+10,12	Na6xb4 c5xb4 d2xe3 Kf6f5 Nd1f2 f4xe3 Re8xe3 Kf5f4 Re3f3+ Kf4e5 Nf2g4+ Ke5d4 Rf3f4+
   9	00:00	     698.847	1.801.152	+10,80	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 Kf5g4 Ra8xa2 f4xe3 Kg7xh6
   9	00:00	     819.061	1.861.502	+10,80	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 Kf5g4 Ra8xa2 f4xe3 Kg7xh6
  10+	00:00	   1.003.214	1.910.883	+11,10	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 Kf5g4 Ra8xa2 f4xe3 Kg7xh6
  10+	00:00	   1.003.214	1.910.883	+11,10	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 a3a2 Re8a8 Kf5g4 Ra8xa2 f4xe3 Kg7xh6
  10	00:00	   1.668.775	1.965.577	+11,19	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 Kg4xh4 e3xf4
  10	00:01	   1.977.475	2.005.552	+11,19	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 Kg4xh4 e3xf4
  11	00:01	   3.640.241	2.057.795	+11,45	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 f4xe3 Nd1xe3+ Kg4f4 Ne3g2+ Kf4f5 Ng2e3+ Kf5f6
  11	00:03	   7.245.237	2.132.833	+11,45	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 f4xe3 Nd1xe3+ Kg4f4 Ne3g2+ Kf4f5 Ng2e3+ Kf5f6
  12+	00:03	   7.855.266	2.134.583	+11,75	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 f4xe3 Nd1xe3+ Kg4f4 Re8e6
  12+	00:03	   7.855.266	2.134.583	+11,75	Na6xb4 c5xb4 d2xe3 Kf6f5 Kg8g7 d6d5 Bc2b3 Kf5g4 Kg7xh6 f4xe3 Nd1xe3+ Kg4f4 Re8e6
  12	00:06	  13.075.201	2.149.819	+12,37	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 c6c5 Ra8xa2 b7b5 e3xf4 c5c4 Ra2a7+ Ke7d8 Ra7a8+ Kd8d7 Kg8g7
  12	00:07	  15.172.936	2.146.708	+12,37	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 c6c5 Ra8xa2 b7b5 e3xf4 c5c4 Ra2a7+ Ke7d8 Ra7a8+ Kd8d7 Kg8g7
  13+	00:08	  18.851.221	2.148.777	+12,67	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 c6c5 Ra8xa2 b7b5 e3xf4 c5c4 Ra2a7+ Ke7d8 f4f5 b4b3 f5f6 d6d5 f6f7
  13+	00:08	  18.851.221	2.148.777	+12,67	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 c6c5 Ra8xa2 b7b5 e3xf4 c5c4 Ra2a7+ Ke7d8 f4f5 b4b3 f5f6 d6d5 f6f7
  13	00:18	  39.036.500	2.105.301	+12,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 d6d5 Ra8xa2 Ke7d7 Kg8g7 d5d4 Ne3f5 c6c5 Bc2a4+ Kd7e6 Nf5xh6
  13	00:20	  43.273.869	2.118.360	+12,75	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 d6d5 Ra8xa2 Ke7d7 Kg8g7 d5d4 Ne3f5 c6c5 Bc2a4+ Kd7e6 Nf5xh6
  14+	00:22	  48.747.649	2.134.871	+13,05	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 d6d5 Ra8xa2 Ke7d7 Kg8g7 d5d4 Ne3f5 c6c5 Bc2b3
  14+	00:22	  48.747.649	2.134.871	+13,05	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 d6d5 Ra8xa2 Ke7d7 Kg8g7 d5d4 Ne3f5 c6c5 Bc2b3
  14	00:41	  88.001.456	2.109.132	+13,10	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 Ke7e6 Ra8xa2 d6d5 Kg8g7 Ke6e5 Kg7xh6 Ke5f4 Ne3g2+ Kf4e5 d3d4+ Ke5f6
  14	00:53	 114.541.200	2.135.050	+13,10	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 Ke7e6 Ra8xa2 d6d5 Kg8g7 Ke6e5 Kg7xh6 Ke5f4 Ne3g2+ Kf4e5 d3d4+ Ke5f6
  15+	00:57	 122.486.884	2.142.165	+13,40	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 Ke7e6 Ra8xa2 d6d5 Ne3g4
  15+	00:57	 122.486.884	2.142.128	+13,40	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 f4xe3 Nd1xe3 Ke7e6 Ra8xa2 d6d5 Ne3g4
  15	01:47	 225.446.606	2.108.061	+13,47	Na6xb4 c5xb4 d2xe3 a3a2 Re8f8+ Kf6e7 Rf8a8 Ke7e6 Ra8xa2 d6d5 Ra2a7 Ke6f5 Ra7xb7 Kf5g4 Kg8g7 Kg4xh5 Rb7xb4 f4xe3 Nd1xe3
  15	02:17	 292.962.134	2.135.370	+14,48	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 Be1xh4 Re8e6+ Kf6g5 f5f6 d4d3 f6f7 Kg5f5 Re6e8 Bh4e7 Bc2xd3+ Kf5g4 Re8xe7 a3a2 f7f8Q a2a1Q Qf8f5+
  15	02:19	 297.333.682	2.136.263	+14,48	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 Be1xh4 Re8e6+ Kf6g5 f5f6 d4d3 f6f7 Kg5f5 Re6e8 Bh4e7 Bc2xd3+ Kf5g4 Re8xe7 a3a2 f7f8Q a2a1Q
  16+	02:22	 303.037.360	2.134.998	+14,78	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 Be1xh4 Re8e6+ Kf6g5 f5f6 d4d3 f6f7 Kg5f5 Re6e8 Bh4e7 Bc2xd3+ Kf5g4 Re8xe7 a3a2 Nd1e3+ Kg4xh5 f7f8Q
  16+	02:22	 303.037.360	2.134.983	+14,78	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 Be1xh4 Re8e6+ Kf6g5 f5f6 d4d3 f6f7 Kg5f5 Re6e8 Bh4e7 Bc2xd3+ Kf5g4 Re8xe7 a3a2 Nd1e3+ Kg4xh5 f7f8Q
  16	02:38	 340.643.605	2.143.963	+16,15	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4 Qf3h1+ Kh4g5 Re7g7+ Qa1xg7+ Kg8xg7
  16	03:09	 407.880.749	2.148.912	+16,15	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4 Qf3h1+ Kh4g5 Re7g7+ Qa1xg7+ Kg8xg7
  17+	03:25	 441.141.537	2.150.818	+16,45	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4 Re7e4+
  17+	03:25	 441.141.537	2.150.818	+16,45	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4 Re7e4+
  17+	03:46	 491.151.398	2.165.475	+18,45	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4
  17+	03:46	 491.151.398	2.165.475	+18,45	d3d4 b7xa6 d2xe3 Bb4e1 e3xf4 c5xd4 f4f5 d4d3 Bc2xd3 Be1xh4 Re8e6+ Kf6g5 f5f6 Kg5xh5 f6f7 Bh4e7 Re6xe7 a3a2 f7f8Q a2a1Q Qf8f3+ Kh5h4
  17	04:16	 556.152.003	2.169.528	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2
  17	04:41	 615.458.796	2.184.236	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2
  18	04:47	 628.042.280	2.187.226	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2
  18	06:02	 801.482.049	2.208.864	+M9	d3d4 b7xa6 d2xe3 Bb4e1 d4d5 c6xd5 e3xf4 d5d4 e2e4 Be1xh4 Bc2b3 c5c4 Bb3xc4 d6d5 Bc4xd5 a3a2
  19	06:14	 830.318.382	2.218.661	+M7	d3d4 b7xa6 d4d5 c6xd5 Bc2a4 a3a2 Nd1c3 Bb4xc3 Ba4d7 a2a1Q Bd7g4 e3xd2
However, Spike 1.2 did not output the last move of the checkmates.

------------

It is incredible how engines prune so well given the huge number of ways to play 13 plies in this position: around 5.438633e+16 (standard deviation of 1.289002e+13) after a Monte Carlo perft run with Nebiyu 1.42.

Regards from Spain.

Ajedrecista.
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