Stockfish 8 Failed To Solve This Chess Puzzle

[Sean Evans]

It is a very difficult puzzle due to the unorthodox selection of new pieces on both sides and the use of squares. The person that created this puzzle is very creative, I wish I had that level of creativity at chess

Sean

[Sergei S. Markoff]

SmarThink r2578:

Code: Select all

3 301 0 821 g4f6 h7g6 d1h5 g6f6 d7d8q f6f5 d8d7 f5e4 d7c6 e4d4 c6a6 c3c2
3 409 0 1011 g4f6 h7g6 d1h5 g6f6 d7d8q f6g7 d8d7 g7g8 d7c8 g8g7 c8a6 c3c2
4 344 1 1933 g4f6 h7g7 f6h5 g7g6 h5f4 g6g7 d7d8q g5f7 d6d7 f7d8 f4e6 d8e6
4 214 1 2314 g4f6 h7g7 f6h5 g7g6 h5f4 g6g7 d7d8q g5f7 d6d7 f7d8 f4e6 d8e6
4 0 1 2779 g4f6 h7g7 f6h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6
5 0 1 3490 g4f6 h7g7 f6h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6 h5f4 g6g7 f4h5 g7g6
6 -14 1 4760 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
6 -42 1 5308 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
6 -98 2 5820 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
6 -98 2 6312 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
6 0 2 6491 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4f5 d1c2 f5g4 c2d1 g4f5 d1c2 f5g4 c2d1 g4f5 d1c2 f5g4
7 -13 2 7004 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
7 -39 2 7720 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
7 -91 2 8300 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
7 -195 2 8979 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
7 -403 2 10115 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 c2d1 g4g3 f4h5 g3f2 d7d8q g5f7 d6d5 f7d8
7 -641 3 16167 g4f6 h7g7 f6h5 g7g6 h5f4 g6f5 d1c2 f5g4 f4g2 c5c4 d6d5 a6c7 d5c4 e3e2 d7d8q
7 -640 3 16337 d1c2 h7g7 g4e3 g5f7 d6d5
7 -574 3 16566 d1c2 h7g7 g4e3 g5f7 d6d5
7 -523 4 20666 d1c2 h7g7 g4e3 g5f7 d6c6 f7d8 c6b6 a6b8 b6c7 b8c6
7 -522 4 22702 g4e3 b4a5
7 -465 4 23910 g4e3 b4a5 d6e7
7 -459 5 24882 g4e3 b4a5 d6e7 a6b4 d7d8q a5d8 e7d8 g5e4
8 -495 6 29033 g4e3 b4a5 d6e7 a6b4 d1g4 b4c6 e7d6 c6d4 d6c5 c3c2
8 -494 7 33580 d1e2 c5c4 d6d5 b4a5 g4e3 a6b4 d5c4 c3c2 e3c2
8 -483 8 42183 d1e2 b4a5 g4e3 a6b4 d6c5 g5f7 e2d1 h7g6
9 -529 11 65225 d1e2 g5f7 d6e7 h7g7 e2a6 c3c2
9 -528 13 73080 d6c6 g5f7 g4e3 f7d8 c6b6 a6b8 b6c7 b8c6 d1c2 h7g7 c2e4
9 -528 13 76539 d6c6 a6b8 c6c7 b8d7 c7d7 g5e4 d1c2 h7g7 c2e4 e3e2
9 -527 16 88139 g4e3 b4a5 d6e7 a6b4 d1g4 b4c6 e7d6 c6d4 d6c5 c3c2
9 -496 17 93400 g4e3 b4a5 d6e7 a6b4 d1a4 g5e4 g3g4 h7g6 d7d8q a5d8 e7d8
10 -539 22 121714 g4e3 b4a5 d1e2 a6b8 d6e7 b8c6 e7d6 c6d4 e2d3 h7g7 d6c5 g5e6 c5c4 g7f7
11 -495 32 171281 g4e3 b4a5 d1e2 a6b8 d6e7 b8c6 e7d6 c6d4 e2d3 h7g7 d6c5 g5e6 c5c4 g7f7 e3d5
11 -495 37 187868 g4e3 b4a5 d1e2 a6b8 d6e7 b8c6 e7d6 c6d4 e2d3 h7g7 d6c5 g5e6 c5c4 g7f7 e3d5 c3c2
12 -532 60 294678 g4e3 b4a5 d6c6 a6b8 c6b5 a5d8 d1g4 h7g7 b5c5 h6h5 g4f5 g7f6 c5c4 c3c2 f5c2 b8d7 e3d5 f6g7
13 -557 179 695243 g4e3 b4a5 d1e2 a6b8 e2d3 h7g7 d3f5 g7f6 d6c5 g5e6 c5d5 e6g7 f5h3 f6e7 d5c4 e7d6 e3f5 g7f5 h3f5 b8d7
14 -560 396 1352389 g4e3 b4a5 d6d5 h7g7 d5c4 a6b8 d1a4 g5e4 e3f5 g7f6
15 -554 772 2371453 g4e3 b4a5 d1a4 g5e4 d6d5 e4g3 d5c4 a5d8 c4b5 a6c7 b5c5 h7g7 c5c4 h6h5 e3d1 h5h4 d1c3 h4h3
15 -553 822 2512098 d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 d1c2 h7h8 g4e3 c7g3 d7c6 h6h5 c6b5
15 -515 847 2554443 d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 d1c2 h7h8 g4e3 c7g3 d7c6 h6h5 c2d1 h5h4 c6b5 g3f2 e3d5
15 -413 941 2711157 d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 g4e3 c7g3 e3d5 g3e5 d7c6 e5d4 c6b5 a6b8 b5c4 h6h5 d5c3 d4c3
16 -405 1034 2934771 d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 g4e3 c7g3 e3d5 g3e5 d7c6 e5d4 c6b5 a6b8 b5c4 h6h5 d5c3 d4c3
17 -378 1179 3365300 d7d8q g5f7 d6e7 f7d8 e7d8 b4a5 d8d7 a5c7 g4e3 c7g3 e3d5 g3e5 d7c6 e5d4 c6b6 a6b4 d5b4 c5b4 b6b5
17 -282 1737 4675181 d7d8q g5f7 d6e7 f7d8 e7d8 c5c4 g4e3 b4d6 e3c4 d6g3 c4e3 a6c5 d1c2 h7h8 c2d1 g3f4 e3c2 h8g7 d1h5 g7f6
18 -282 1803 4901522 d7d8q g5f7 d6e7 f7d8 e7d8 c5c4 g4e3 b4d6 e3c4 d6g3 c4e3 a6c5 d1c2 h7h8 c2d1 g3f4 e3c2 h8g7 d1h5 g7f6
18 -281 1895 5226010 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q g5f7 d6e6 f7d8 e6f5 e3e2 c2e4
18 -260 1962 5443626 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q g5f7 d6e6 f7d8 e6f5 e3e2 c2e4
18 103 22150 83580081 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8d7 g4g3 c2d1 h6h5 d7g7 g3h4 g7f6 c5c4 d6d5
19 115 27134 104244902 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8f6 g4g3 f6e5 g3f2 e5f4 f2e2 f4c4 e2e1 c4a6
19 227 30715 119619041 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8e8 g4f3 c2d1 f3f2 e8h5 g5e4 d6e5 e4g3 h5h2 f2e1 d1f3
19 488 47901 194186721 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8e8 c5c4 d6c6 b4a3 c2d1 g4h3 e8e3 a6b4 c6b5 b4d3 e3d4 a3b2
20 488 50242 202674839 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8e8 c5c4 d6c6 b4a3 c2d1 g4h3 e8e3 a6b4 c6b5 b4d3 e3d4 a3b2
21 458 51813 209148508 g4f6 h7g7 f6h5 g7g6 d1c2 g6h5 d7d8q h5g4 d8e8 c5c4 d6c6 b4a3 c2d1 g4h3 e8e3 a6b4 c6b5 b4d3 e3d4 a3b2

[peter]

It's said it was composed by Gijs van Breukelen, isn't it?

8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

Analysis by Chiron 4 64bit:

1.Bc2+ Kg7 2.Nxe3 Ba5 3.Nf5+ Kg6 4.Ne3+ Kf7 5.g4 Nb4 6.Kxc5 Nxc2
-+ (-2.36) Depth: 7/23 00:00:01 137kN
...
1.d8R Nf7+ 2.Ke7 Nxd8 3.Kxd8 Ba5+ 4.Ke7 e2 5.Bxe2 Nb4 6.Ne3 Bc7 7.Kf6 Bxg3 8.Nc2 Nd5+ 9.Kf5 Nf4 10.Bd1 h5 11.Ne3 h4 12.Bc2 Kg7 13.Kg4 Kf6 14.Bb1 Ke5 15.Bc2 Kf6 16.Bb1 Ke5 17.Bc2 Kf6
-+ (-3.81) Depth: 35/55 00:01:16 1595MN
...
1.Kc6 Nb8+ 2.Kc7 Nxd7 3.Kxd7 e2 4.Bxe2 Kg7 5.Bd1 Ne4 6.Ke6 Nxg3 7.Ne5 h5 8.Nf3 Nf1 9.Nh4 Kh8 10.Ke5 Ne3
-+ (-3.79) Depth: 41/62 00:02:27 3188MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Nxd8+ 6.Kf5 e2 7.Be4 e1N 8.Bd5 c2 9.Bc4 c1N 10.Bb5 Nc7 11.Ba4 Nf3 12.Bd1
-+ (-3.59) Depth: 41/62 00:03:28 4559MN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Nxd8+ 6.Kf5 e2 7.Be4 e1N 8.Bd5 c4 9.Bxc4 Nf3 10.Be2
=/+ (-0.58) Depth: 41/64 00:05:46 7669MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Nxd8+ 6.Kf5 e2 7.Be4 e1N 8.Bd5 c4 9.Bxc4 Nf3 10.Be2
+/- (1.05) Depth: 41/64 00:06:49 9078MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Nxd8+ 6.Kf5 e2 7.Be4 e1N 8.Bd5 c2 9.Bc4 c1N 10.Bb5 Nc7 11.Ba4 Nb3 12.Bxb3 Nc2 13.Bxc2
+- (3.49) Depth: 41/64 00:07:53 10498MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Kc6 Nf3 6.Qg8+ Kh3 7.Qe6+ Kg2 8.Qxe3 Nd4+ 9.Kb7 Nxc2 10.Qe2+ Kxg3 11.Qxc2 Nb8 12.Kxb8 h5 13.Qg6+ Kf2 14.Qc2+ Kg3 15.Qg6+ Kf2 16.Qc2+ Kg3
+- (7.52) Depth: 41/88 00:25:38 36113MN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Ba3 5.Bd1+ Kg6 6.Qg8+ Kf6 7.Qh8+ Kg6 8.Qe8+ Kg7 9.Qe7+ Kg8 10.Kd7 Nf7 11.Qe8+ Kg7 12.Qxe3 Nb8+ 13.Kc7 Na6+ 14.Kb6 Bb2 15.Qe7 Kg6 16.Kxa6
+- (8.42) Depth: 46/90 00:31:09 43547MN

[flok]

Embla sticks to h5f4:

Code: Select all

info depth 1 seldepth 4 score cp 194 time 1 nodes 36 pv h5f4 g6h7 d7d8=q
info depth 2 seldepth 9 score cp 194 time 2 nodes 244 pv h5f4 g6g7 d7d8=q
info depth 3 seldepth 9 score cp 85 ebf 6.26 time 9 nodes 1655 pv h5f4 g6g7 d7d8=q
info depth 3 seldepth 6 score cp 83 ebf 0.99 time 10 nodes 1857 pv h5f4 g6f5 d1c2 f5g4 d7d8=q g4g3
info depth 4 seldepth 10 score cp 0 ebf 1.02 time 15 nodes 3311 pv h5f4 g6f5 d1c2 f5g4 d7d8=q g4g3
info depth 4 seldepth 11 score cp 0 ebf 2.20 time 19 nodes 4291 pv h5f4
info depth 5 seldepth 10 score cp 0 ebf 1.53 time 31 nodes 7707 pv h5f4 g6f5 d1c2 f5g4 c2d1 g4f5
info depth 6 seldepth 12 score cp -84 ebf 2.43 time 47 nodes 13476 pv h5f4 g6f5 d1c2 f5g4 c2d1 g4f5
info depth 6 seldepth 15 score cp -427 ebf 3.64 time 156 nodes 58730 pv h5f4 g6f5 f4d5 g5f7 d6e7 f5g6 d1c2 g6g7 d5e3
info depth 7 seldepth 17 score cp -440 ebf 2.80 time 232 nodes 103894 pv h5f4 g6f5 f4d5 g5f7 d6e7 f5g6 d1c2 g6g7 d5e3 c5c4 e7e8
info depth 8 seldepth 21 score cp -440 ebf 1.95 time 468 nodes 276173 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 9 seldepth 19 score cp -440 ebf 1.65 time 629 nodes 399371 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 10 seldepth 21 score cp -440 ebf 1.11 time 896 nodes 611625 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 11 seldepth 22 score cp -440 ebf 1.90 time 1462 nodes 1056019 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 12 seldepth 26 score cp -440 ebf 2.00 time 2532 nodes 1908127 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 13 seldepth 26 score cp -440 ebf 2.75 time 6685 nodes 5263475 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 14 seldepth 28 score cp -440 ebf 2.11 time 11531 nodes 9057836 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 15 seldepth 28 score cp -440 ebf 1.42 time 20057 nodes 15809772 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 16 seldepth 32 score cp -440 ebf 2.06 time 40350 nodes 31901322 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 17 seldepth 33 score cp -440 ebf 2.15 time 79912 nodes 62983395 pv h5f4 g6g7 f4h5 g7g6 h5f4
info depth 18 seldepth 34 score cp -441 ebf 2.95 time 258162 nodes 203427815 pv h5f4 g6f5 f4d5 g5e4 d6c6 a6b8 c6c7 b8d7 d5e3 f5e6 d1g4 e6f7 g4d7 e4g3 c7b6 h6h5 b6b5 h5h4 b5a4 f7f8 e3c2 f8e7 d7c6
info depth 19 seldepth 35 score cp -443 ebf 3.22 time 674046 nodes 525064490 pv h5f4 g6f5 f4d5 g5e4 d6c6 a6b8 c6c7 b8d7 d5e3 f5e6 d1g4 e6f7 g4d7 e4g3 c7c6 h6h5 c6d5 h5h4 d7e6 f7g6 d5c4 g6f6 c4d5 f6g7

[Sean Evans]

Hi, I do not see any chess engines solving the puzzle to checkmate for White on this thread or am I missing something

[Vinvin]

Hi, I do not see any chess engines solving the puzzle to checkmate for White on this thread or am I missing something

I think there's no immediate checkmate. Black can gives material to avoid the direct mate.

[Sean Evans]

Hi, I do not see any chess engines solving the puzzle to checkmate for White on this thread or am I missing something

I think there's no immediate checkmate. Black can gives material to avoid the direct mate.

Recall, the thread subject is: "Stockfish 8 Failed To Solve This Chess Puzzle"

Yes, I know black can delay mate by imposing pieces, regardless there is still a final checkmate. It appears that checkmate in this solvable chess puzzle is beyond the horizon of any chess program. At least so far on this thread If CCC members cannot find checkmate, who can?

[Vinvin]

Hi, I do not see any chess engines solving the puzzle to checkmate for White on this thread or am I missing something

I think there's no immediate checkmate. Black can gives material to avoid the direct mate.

Recall, the thread subject is: "Stockfish 8 Failed To Solve This Chess Puzzle"

Yes, I know black can delay mate by imposing pieces, regardless there is still a final checkmate. It appears that checkmate in this solvable chess puzzle is beyond the horizon of any chess program. At least so far on this thread If CCC members cannot find checkmate, who can?

It's mate in 39 (77 half-plies), http://www.talkchess.com/forum/viewtopi ... 978#710978
Out of reach for current engines.

[Sean Evans]

It's mate in 39 (77 half-plies), http://www.talkchess.com/forum/viewtopi ... 978#710978 Out of reach for current engines.

Ah, so for the first time CCC members and their chess engines cannot solve a chess puzzle

Anyone happen to know, which chess databases have the solved puzzle? Does anyone own the endgame study database HHdbIV

Sean

[Leo]

Hi, I do not see any chess engines solving the puzzle to checkmate for White on this thread or am I missing something

I think there's no immediate checkmate. Black can gives material to avoid the direct mate.

Recall, the thread subject is: "Stockfish 8 Failed To Solve This Chess Puzzle"

Yes, I know black can delay mate by imposing pieces, regardless there is still a final checkmate. It appears that checkmate in this solvable chess puzzle is beyond the horizon of any chess program. At least so far on this thread If CCC members cannot find checkmate, who can?

It's mate in 39 (77 half-plies), http://www.talkchess.com/forum/viewtopi ... 978#710978
Out of reach for current engines.

I wouldn't doubt it if Tal did find it. I remember Fischer talking about looking 40 moves deep once.