Stockfish 8 Failed To Solve This Chess Puzzle

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Sean Evans
Posts: 1777
Joined: Thu Jun 05, 2008 10:58 pm
Location: Canada

Stockfish 8 Failed To Solve This Chess Puzzle

Post by Sean Evans »

Stockfish 8 Failed To Solve This Chess Puzzle, But Mikhail Tal Solved!

Published on Feb 6, 2017
A very complex chess puzzle which is known as "Plaskett's Puzzle".

https://www.youtube.com/watch?v=5say2stC7eQ
yanquis1972
Posts: 1766
Joined: Wed Jun 03, 2009 12:14 am

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by yanquis1972 »

[d]8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1
flok

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by flok »

What is the solution?
yanquis1972
Posts: 1766
Joined: Wed Jun 03, 2009 12:14 am

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by yanquis1972 »

yeah the video linked isn't exactly the quickest or clearest...i dont have the full line yet but this vid seems better -- https://www.youtube.com/watch?v=ncdsvKP0pPA

critical position seems to be [d]8/3P4/n2K2kp/2p3nN/1b6/2p1p1P1/8/3B4 w - - 0 3
yanquis1972
Posts: 1766
Joined: Wed Jun 03, 2009 12:14 am

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by yanquis1972 »

sorry, key move there is Bc2+ (after Nf6+ Kg7 Nh5+ Kg6)

tried the above position with houdini tactical & sting 7.3 (is there a newer version?); the latter found it, houdini can't in whats typically a reasonable amount of time for tactical mode
yanquis1972
Posts: 1766
Joined: Wed Jun 03, 2009 12:14 am

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by yanquis1972 »

better result on another try for houdini:

8/3P4/n2K2kp/2p3nN/1b6/2p1p1P1/8/3B4 w - - 0 1

Analysis by Houdini 5.01T

3.Nf4+ Kf5 4.Nd5 Ne4+ 5.Ke7 c4+ 6.Kf7 Nd6+ 7.Kg7 Ba5 8.Nxe3+ Ke4 9.Ng4 Nc5 10.Bc2+ Kd5
Black has a decisive advantage: -+ (-2.80) Depth: 7/27 00:00:00 299kN
Black is winning: -+ (-3.56) Depth: 11/31 00:00:01 2229kN
3.d8N Ba5 4.Nc6 Bc7+ 5.Kd5 Kf7 6.Nf4 Bxf4 7.gxf4 c2 8.Bxc2 e2 9.fxg5 e1Q
Black is winning: -+ (-3.74) Depth: 12/33 00:00:01 4883kN
3.Nf4+ Kf5 4.Kd5 Nf7 5.Ng2 Nc7+ 6.Kc6 Ke4 7.Nf4 Ne6 8.Nxe6 Ne5+ 9.Kd6 c4+ 10.Nc5+ Kd4 11.Ke6 Nc6
Black has a decisive advantage: -+ (-3.45) Depth: 12/33 00:00:01 5705kN
Black is winning: -+ (-3.93) Depth: 13/38 00:00:01 14935kN
3.Kd5 Nf7 4.Nf4+ Kf6 5.Ke4 Nb8 6.Kxe3 Nxd7 7.Kd3 Nd6 8.Nd5+ Kg5 9.Nxc3 Ne5+ 10.Kc2 Bxc3 11.Kxc3 Nf5
Black is clearly winning: -+ (-4.39) Depth: 14/38 00:00:02 32234kN
3.Nf4+ Kf5 4.Kd5 Nf7 5.Bc2+ Kf6 6.Bb3 Nb8 7.Ba4 Ke7 8.Ke4 Nxd7 9.Kxe3 Nf6 10.Kd3 Ne5+ 11.Ke2 Kd6 12.Bc2 Nd5 13.Be4 Nxf4+
Black is clearly winning: -+ (-4.29) Depth: 15/40 00:00:03 42676kN
3.Kd5 Nf7 4.Nf4+ Kf5 5.Bc2+ Kf6 6.Ne2 Nb8 7.Ba4 c2 8.g4 Kg5 9.Ke6 Nd8+ 10.Kd6 Kxg4 11.Bxc2 Kf3 12.Bd1 Kf2 13.Nf4 c4+ 14.Kd5 Nxd7 15.Kxc4 Be7 16.Bh5 Nf6 17.Bd1 Ke1 18.Kd3 Kxd1 19.Kxe3
Black is clearly winning: -+ (-4.49) Depth: 16/40 00:00:04 54993kN
Black is clearly winning: -+ (-4.81 --) Depth: 18/50 00:00:08 128MN, tb=1
3.Nf4+ Kf5
Black is clearly winning: -+ (-4.67) Depth: 18/50 00:00:08 133MN, tb=1
Black is clearly winning: -+ (-5.21 --) Depth: 20/52 00:00:23 409MN, tb=7
3.Kd5 Nf7
Black is clearly winning: -+ (-5.05) Depth: 20/52 00:00:23 414MN, tb=7
Black is clearly winning: -+ (-5.71 --) Depth: 22/52 00:00:52 945MN, tb=102
3.Bc2+
Black is clearly winning: -+ (-5.26 ++) Depth: 22/52 00:00:52 945MN, tb=102
White is better: +/- (1.15 ++) Depth: 22/52 00:01:00 1082MN, tb=252
peter
Posts: 3185
Joined: Sat Feb 16, 2008 7:38 am
Full name: Peter Martan

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by peter »

Hi Folkert!

I have this in my database:

[pgn]
[Event "?"]
[Site "?"]
[Date "2015.09.20"]
[Round "?"]
[White "Plaskett's, Puzzle"]
[Black "Author Unknown"]
[Result "1-0"]
[Annotator "Martan,Peter"]
[FEN "8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1"]
[SetUp "1"]

1. Nf6+ Kg7 2. Nh5+ Kg6 3. Bc2+ Kxh5 4. d8=Q Kg4 (4... Nf7+ $6 {youtube} 5. Ke6
Nxd8+ 6. Kf5 e2 7. Be4 e1=N 8. Bd5 c2 9. Bc4 c1=N 10. Bb5 Nc6 11. Bxc6 Nc7 12.
Ba4 Nb3 13. Bxb3 Nd5 14. Bd1+ Nf3 15. Bxf3#) 5. Bd1+ Kxg3 (5... Kh3 $5 6. Qc8+
Kxg3 7. Qg4+ Kf2 8. Qe2+ Kg1 9. Qxe3+ Kg2 10. Qe2+ Kg3 11. Qxa6 c2 12. Bxc2 Nf3
13. Qe2 Nd4 14. Qe3+ Kg2 15. Be4+ Kf1 16. Ke5 Ba5 17. Bf5 Bc7+ 18. Ke4 Nxf5 19.
Kxf5 h5 20. Ke4 Kg2 21. Qf3+ Kh2 22. Qxh5+ Kg2 23. Qf3+ Kg1 24. Qe2 Bg3 25. Kf3
Bf2 26. Qxf2+ Kh1 27. Qg2#) 6. Qe8 c4+ 7. Kc6 Kf4 8. Qg8 Nc5 9. Qxc4+ Nge4 10.
Kd5 Ba3 11. Bc2 e2 12. Qxe2 Nf6+ 13. Kd4 Ncd7 14. Qe3+ Kg4 15. Qe6+ Kg5 (15...
Kf3 16. Qf5+ Kg3 17. Kxc3 h5 18. Ba4 Nc5 19. Qe5+ Kh3 20. Bc2 Ng4 21. Qxh5+ {
7:#16}) 16. Kxc3 Kf4 17. Qf5+ Ke3 18. Qd3+ Kf4 19. Qd4+ Kg5 20. Kd2 Bc5 21. Qd3
Kh4 22. Qf5 Bb4+ 23. Ke2 Bc3 24. Qf2+ Kh5 25. Qf3+ Ng4 26. Qxc3 Nde5 27. Qd2
Kh4 28. Qf4 Nd7 29. Bf5 Ndf6 30. Bxg4 Nxg4 31. Kf3 h5 32. Ke4 Kh3 33. Qf1+ Kg3
34. Qg1+ Kh3 35. Kf4 h4 36. Qxg4+ Kh2 37. Kf3 h3 38. Kf2 Kh1 39. Qxh3# 1-0

[/pgn]
Last edited by peter on Mon Apr 03, 2017 11:10 pm, edited 1 time in total.
Peter.
Dann Corbit
Posts: 12538
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by Dann Corbit »

Sting says:

Code: Select all

Analysis of Q:\pl-puz.epd   
2017-04-03 1:34:21 PM Level: 600 Seconds
Analyzing engine: Sting-sf-73

 1 Nf6+;                
    Searching move: Ng4-f6
    Best move (Sting-sf-73): Ng4-f6
    Identical moves! Found in: 02:09
      2	00:00	         183	695	+5.13	Bc2+ Kg7 d8Q
      3	00:00	         894	3,386	-0.36	Nf6+ Kg6 Bc2+ Kxf6 d8Q+ Kf7
      4	00:00	       1,456	5,494	-0.36	Nf6+ Kg6 Bc2+ Kxf6 d8Q+ Kf7
      5+	00:00	       1,529	5,769	-0.16	Nf6+
      5+	00:00	       1,568	5,894	+0.76	Nf6+
      5+	00:00	       1,667	6,266	+0.76	Nf6+
      5	00:00	       1,932	7,235	+0.84	Nf6+ Kg6 Bc2+ Kxf6 d8Q+ Kg7 Qe7+ Nf7+ Kd5
      6+	00:00	       2,254	8,441	+1.05	Nf6+
      6	00:00	       2,603	9,712	+1.05	Nf6+ Kg6 Bh5+ Kxf6 d8Q+ Kf5 Qc8+ Ke4 Qxa6
      7+	00:00	       3,028	11,298	+1.17	Nf6+
      7	00:00	       4,352	16,118	+1.17	Nf6+ Kg6 Bh5+ Kxf6 d8Q+ Kf5 Qc8+ Ke4 Bg6+ Kf3 Qxa6 Kxg3
      8+	00:00	       4,819	17,782	+1.41	Nf6+
      8+	00:00	       4,889	18,040	+1.41	Nf6+
      8+	00:00	       5,583	20,525	+2.90	Nf6+
      8	00:00	       7,434	27,131	+3.15	Nf6+ Kg6 Bh5+ Kg7 d8Q Nf7+ Bxf7 Kxf7 Kd5
      9-	00:00	      16,110	57,330	+2.97	Nf6+
      9-	00:00	      17,845	63,505	+2.90	Nf6+
      9-	00:00	      26,894	93,381	+0.51	Nf6+
      9	00:00	      30,154	103,979	 0.00	Nf6+ Kg7 Nh5+ Kg6 Nf4+ Kg7 Nh5+
     10-	00:00	      51,178	171,738	-0.12	Nf6+
     10-	00:00	      57,451	191,503	-0.24	Nf6+
     10-	00:00	      83,884	266,298	-1.10	Nf6+
     10	00:00	     122,561	370,274	-1.29	Nxe3 Ba5 Be2 Ne4+ Ke5 Nb8 Kxe4 Nxd7 Bb5 Nf6+ Kd3
     11-	00:00	     185,714	535,198	-1.41	Nxe3
     11-	00:00	     224,593	629,112	-1.53	Nxe3
     11-	00:00	     361,783	922,915	-1.98	Nxe3
     11	00:00	     421,292	1,037,665	-1.93	Nxe3 Ba5 Be2 Nb8 Bd3+ Kg8 Bf5 Bd8 Kxc5 Kf7 Kd4 Ke7 Nd5+ Kd6
     12-	00:00	     549,290	1,259,839	-2.06	Nxe3
     12	00:00	     632,763	1,381,578	-2.10	Nxe3 Ba5 Be2 Nb8 Ke7 Nxd7 Bd3+ Kg8 Kxd7 Nf3 Kd6 Bb4 Bc2 Nd4 Kd5 Nxc2 Nxc2
     13-	00:00	     905,667	1,751,773	-2.22	Nxe3
     13	00:00	     970,565	1,838,191	-2.10	Nxe3 Ba5 Be2 Nb8 Bd3+ Kg8 Bf5 Bd8 Kxc5 Kf7 Kd6 Kf6 g4 Nf7+ Kd5
     14-	00:00	   1,220,083	2,133,012	-2.18	Nxe3
     14-	00:00	   1,374,461	2,192,122	-2.26	Nxe3
     14-	00:00	   1,705,577	2,500,846	-2.38	Nxe3
     14	00:00	   2,112,244	2,797,674	-2.50	Nxe3 Ba5 Be2 Nb8 Bd3+ Kg8 Bf5 Bd8 Kd5 Kf7 Kxc5 c2 Nxc2 Ke7 Kd5 Nxd7 Nd4 Nf6+ Kc4
     15-	00:00	   3,000,193	3,405,440	-2.62	Nxe3
     15	00:00	   3,157,975	3,458,899	-2.58	Nxe3 Ba5 Be2 Nb8 Bd3+ Kg8 Bf5 Bd8 Kxc5 Kf7 Kc4 Ne6 Kd5 Nf8 Nd1 c2 Bxc2 Nbxd7 Ne3 Bc7 Nf5 Nf6+ Kd4
     16	00:01	   4,124,504	3,880,060	-2.54	Nxe3 Ba5 Be2 Nb8 Ke7 Bc7 Bb5 Nxd7 Bd3+ Kg8 Kxd7 Bxg3 Nf5 Be5 Kc6 Ne6 Bc2 Kf7 Nxh6+ Kg7
     17-	00:01	   5,196,089	4,315,688	-2.62	Nxe3
     17-	00:01	   6,458,150	4,808,749	-2.70	Nxe3
     17	00:01	   7,581,268	5,112,115	-2.54	Nxe3 Ba5 Be2 Nb8 Bd3+ Kg8 Bb5 Ne4+ Ke7 Nxd7 Kxd7 Nxg3 Bd3 Kf7 Nf5 Nh5 Nxh6+ Kf6 Nf5
     18+	00:01	   9,642,074	5,651,860	-2.46	d8Q
     18+	00:01	   9,999,145	5,694,273	-2.38	d8Q
     18	00:01	  11,043,007	5,748,572	-2.54	d8Q Nf7+ Ke7 Nxd8 Kxd8 e2 Bxe2 Ba5+ Kd7 Nb4 Ne3 Bb6 Bd1 c4 Nc2 Nd3 Kd6 Kg6 Kd5 Kf5 Be2 Ne5 Bxc4 Nxc4 Kxc4
     19+	00:02	  12,081,178	5,960,127	-2.46	d8Q
     19+	00:02	  12,270,107	5,941,940	-2.38	d8Q
     19+	00:02	  12,756,735	6,003,169	-2.26	d8Q
     19	00:02	  14,394,562	6,188,547	-2.46	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Nd5 Be5 Kc6 Nb4+ Nxb4 cxb4 Bc2+ Kg7 Kc5 Bd6+ Kd4 Kf6
     20+	00:02	  15,888,334	6,442,957	-2.38	d8Q
     20-	00:02	  18,154,316	6,645,064	-2.54	d8Q
     20+	00:02	  18,755,666	6,696,060	-2.30	d8Q
     20	00:02	  20,134,115	6,802,065	-2.58	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Kc6 Kg6 Kb6 Nc7 Bc2+ Kf6 Nf5 Be5 Nxh6 Nd5+ Kxc5 Ne3 Be4 Kg5 Nf7+ Kf4 Bd3 Bf6
     21+	00:03	  22,000,510	7,035,660	-2.46	d8Q
     21	00:03	  25,235,709	6,984,696	-2.50	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Kc6 Kg6 Kb6 Nc7 Bc2+ Kf6 Nf5 Bf4 Kxc5 Ke5 Ne7 Ke6 Nf5 h5 Nd4+ Ke5 Kc4 Be3 Nc6+ Kd6
     22+	00:03	  28,309,240	7,247,629	-2.38	d8Q
     22	00:04	  33,377,878	7,450,419	-2.34	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Nd5 Be5 Ke6 Bd4 Kf7 Kh8 Kg6 Nb4 Nxb4 cxb4 Kxh6 Kg8 Kg6 Kf8 Kf5 Ke7 Bc2 Kd6 Ke4
     23-	00:05	  43,200,025	7,855,978	-2.46	d8Q
     23	00:05	  45,326,254	7,922,785	-2.42	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Nd5 Be5 Ke6 Bd4 Kf7 Nb8 Ne7 h5 Bxh5 Nd7 Bd1 Ne5+ Ke6 Nc4 Bc2+ Kh6 Nf5+ Kg5 Kd5
     24-	00:07	  58,744,404	8,179,393	-2.54	d8Q
     24	00:07	  62,218,193	8,310,163	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Nd5 Be5 Ke6 Bd4 Kf7 Nb8 Ne7 h5 Bxh5 Nd7 Bg6+ Kh6 Bc2 Nb6 Ke6 Kg5 Nd5 Nc4 Bd3 Ne5 Bc2 Kg4 Nf6+ Kf4 Nd5+ Kf3
     25-	00:09	  78,811,179	8,514,604	-2.46	d8Q
     25	00:09	  85,848,848	8,661,976	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kd7 Bc7 Nxe3 Bxg3 Nd5 Be5 Ke6 Bd4 Kf7 Nb8 Ne7 h5 Bxh5 Nd7 Bg6+ Kh6 Bc2 Nb6 Ke6 Kg5 Nd5 Nc4 Bd3 Ne5 Bc2 Kg4 Nf6+ Kf4 Nd5+ Kf3
     26	00:17	 172,118,002	9,897,527	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kc8 e2 Bxe2 Nb4 Ne3 Kg6 Kd7 Kg5 Bd1 Bb6 Nc2 h5 Kd6 Ba7 Kc7 Nxc2 Bxc2 Bb8+ Kc6 Bxg3 Kxc5 Be5 Kd5 h4 Ke4 h3 Kf3 h2 Kg2 Bg3
     27	00:21	 212,369,916	9,987,298	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Ke8 e2 Bxe2 Nb4 Ne3 Kg7 Bd1 Bc7 Ke7 Kg6 g4 Kg5 Ke6 Bb8 Nc2 Nd3 Kd5 Nf2 Bf3 Kf4 Bg2 Be5 Kxc5 Nxg4 Kc4 h5 Kd3 h4 Ke2 Bd6 Bf3
     28	00:31	 327,411,975	10,397,331	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kc8 e2 Bxe2 Nb4 Ne3 Kg6 Kd7 Kg5 Bd1 Bb6 Nc2 h5 Kd6 Ba7 Ne1 c4 Nc2 Bb8+ Kc5 Nd3+ Kd4 Nb2 Be2 Bxg3 Kxc3 Be5+ Nd4 Bxd4+ Kxd4 h4 Bf1 Kf4
     29	00:44	 469,339,418	10,657,842	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Ke7 e2 Bxe2 Nb4 Ne3 Bc7 g4 Kg6 Bd1 Kg5 Ke6 Bb8 Nc2 Nd3 Ne3 Nf4+ Kd7 Be5 Kc6 Bd4 Nd5 Nd3 Kb5 Ne1 Nxc3 Bxc3 Kxc5 Nd3+ Kd6 Ne5 Kd5 Kf4 Ke6
     30	01:00	 659,342,450	10,856,054	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Kc8 e2 Bxe2 Nb4 Ne3 Kg6 Kd7 Kg5 Bd1 Bb6 Nc2 h5 Kd6 Ba7 Ne1 c4 Nc2 Nd3 Kd5
     31	01:23	 924,712,326	11,129,446	-2.38	d8Q Nf7+ Ke7 Nxd8 Kxd8 Ba5+ Ke8 e2 Bxe2 Nb4 Ne3 Bc7 Kf7 Bxg3 Kf6 Kh8 Bd1 h5 Kf5 h4 Kg4 Kg7 Bb3 Kf6 Nc2 Nc6 Ne3 Ne5+ Kh3 Kg5 Bc2 Nf3 Bh7 Nd4 Kg2 Be5 Kh3 Bd6 Kg2 Be5
     32+	02:09	1,490,302,085	11,530,472	-2.30	Nf6+
     32+	02:18	1,601,001,979	11,545,160	-2.22	Nf6+
     32+	03:43	2,641,387,350	11,836,718	+3.70	Nf6+
     32	05:49	4,303,089,993	12,327,757	+3.83	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8Q Kg4 Kc6 Ba3 Qd1+ Kxg3 Qe1+ Kf4 Qh4+ Kf3 Bd1+ e2 Qh5+ Kg3 Qxe2 Nb4+ Kxc5 c2 Bxc2 Nxc2+ Kc4 Nf3 Qxc2 Be7 Qg6+ Bg5 Qh5
     33+	06:38	4,949,878,574	12,412,648	+3.95	Nf6+
     33+	07:06	5,305,972,750	12,430,910	+4.08	Nf6+
     33+	08:39	6,384,437,137	12,295,284	+4.94	Nf6+
     33	09:41	7,115,405,887	12,240,210	+4.96	Nf6+ Kg7 Nh5+ Kg6 Bc2+ Kxh5 d8Q Kg4 Kc6 Ba3 Qd1+ Kxg3 Qe1+ Kf4 Qf1+ Kg3
   2017-04-03 1:44:26 PM, Time for this analysis: 00:10:01, Rated time: 02:09

1 of 1 matching moves
2017-04-03 1:44:27 PM, Total time: 12:10:06 AM
Rated time: 02:09 = 129 Seconds
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
peter
Posts: 3185
Joined: Sat Feb 16, 2008 7:38 am
Full name: Peter Martan

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by peter »

Hi Dann!

Deep Shredder 13 does very well here too:
8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 1

Analysis by Deep Shredder 13 x64:

1.Nf6+ Kg6 2.Bh5+ Kxf6 3.d8Q+ Kg7 4.Qd7+ Kh8 5.Qc8+ Kh7
+- (3.16 ++) Depth: 7/17 00:00:00 2kN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Nf4+ Kf5 4.Bc2+ Kg4 5.Bd1+ Kxg3 6.Ne2+ Kg2 7.Nf4+
-+ (-2.47 --) Depth: 11/30 00:00:00 5614kN
1.d8Q
-+ (-2.40 ++) Depth: 11/30 00:00:00 5628kN
1.Nxe3
-+ (-2.47 ++) Depth: 11/30 00:00:00 5753kN
...
1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd4 5.Bd3+ Kg7 6.Kxc5 Ngf3 7.Kd5 Kf6 8.Kd6 Ne1 9.Nd5+ Kg5
-+ (-2.62) Depth: 13/30 00:00:00 7207kN
1.d8Q
-+ (-2.61 ++) Depth: 13/30 00:00:00 7260kN
...
1.d8Q Nf7+ 2.Kd7 Nxd8 3.Nxe3
-+ (-1.94 --) Depth: 23/44 00:00:02 43813kN
1.Nf6+
-+ (-1.93 ++) Depth: 23/44 00:00:02 46939kN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Ng5+
-+ (-1.80 ++) Depth: 23/44 00:00:02 47401kN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Nf7+ 5.Ke6 Ng5+
+- (3.44 ++) Depth: 23/55 00:00:03 73933kN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Qe8 c4+ 6.Kc6 Ba3 7.Bd1+ Kh3 8.Qxe3 Nb4+ 9.Kb5 Nd3 10.Qd4 Bb2 11.Qxc4 Ne1 12.Qg4+ Kh2 13.Qe2+ Ng2 14.Kb4 Kxg3 15.Kb3 Kh2 16.Qe5+ Kg1 17.Qc5+ Kf1 18.Qd4 Ba1 19.Bh5 Bb2 20.Qd6 Kf2 21.Qxh6
+- (3.48) Depth: 23/59 00:00:04 105MN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Bd1+ e2 6.Bxe2+ Kxg3 7.Kc6 Kf2 8.Qd1 Nb8+ 9.Kb7 Ne6 10.Bd3 Nd4 11.Kxb8 h5 12.Qxh5 Ke1 13.Qg5 Kd1 14.Bg6 Ke2 15.Qc1 Kf2 16.Bd3 Kg3 17.Qe3+ Kg4 18.Kb7 Ba3 19.Qe4+ Kg5 20.Qe5+ Kg4 21.Be2+ Kh3 22.Qe3+ Kg2 23.Bd3 Bb4 24.Qf4 Nb3
+- (6.59 ++) Depth: 34/75 00:01:02 1948MN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q Kg4 5.Bd1+ e2 6.Bxe2+ Kxg3 7.Kc6 Kf2 8.Qd1 Nb8+ 9.Kb7 Ne6 10.Kxb8 c2 11.Qf1+ Ke3 12.Qc1+ Kxe2 13.Qxc2+ Bd2 14.Qc4+ Kf3 15.Qxe6 Be3 16.Kb7 Ke2 17.Qd5 Bd4 18.Qh5+ Kd3 19.Qxh6 Kc4 20.Kc6 Kd3 21.Qh5 Ke4 22.Qg4+ Ke5 23.Qg6 Be3 24.Qh5+ Kf4 25.Kd5 Bd4 26.Qh4+ Ke3 27.Qe4+ Kd2 28.Qf4+ Kd1 29.Qf3+ Kc2 30.Qe2+ Kc3 31.Qe1+ Kb3 32.Qc1 Ka2 33.Qc2+ Ka1
+- (8.89) Depth: 40/85 00:05:29 10972MN
Peter.
peter
Posts: 3185
Joined: Sat Feb 16, 2008 7:38 am
Full name: Peter Martan

Re: Stockfish 8 Failed To Solve This Chess Puzzle

Post by peter »

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

Analysis by Fritz 15:
...
1.Nxe3 Ba5 2.Be2 Nb8 3.Ke7 Nc6+ 4.Kd6 Nd8 5.Kxc5 Kg7 6.Bd3 Kf7 7.Kd6 Bb4+ 8.Ke5 Bf8 9.Nd5 Nge6
-+ (-2.27) Depth: 12 00:00:00 763kN
1.d8Q Nf7+ 2.Kd7 Nxd8 3.Kxd8 e2 4.Bxe2 Ba5+ 5.Kd7 Nb4 6.Ne3 c4 7.Bf3 Kg7 8.Be4 Bb6 9.Nc2 Nd3 10.Bd5
-+ (-2.18) Depth: 13 00:00:00 1519kN
...
1.Nf6+ Kg7[] 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q
-+ (-2.12 ++) Depth: 27 00:01:08 909MN
...
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q[]
+- (4.03 ++) Depth: 27 00:04:00 3479MN
1.Nf6+ Kg7 2.Nh5+ Kg6 3.Bc2+ Kxh5 4.d8Q[] Kg4 5.Qf6[] Kxg3 6.Qe5+ Kf3 7.Qf5+ Kg3 8.Bd1 Kg2 9.Qg4+ Kh1 10.Be2 Nf7+ 11.Ke7 Ne5 12.Qh3+ Kg1 13.Qg3+ Kh1 14.Bf1 Nc6+ 15.Kd6
+- (6.74) Depth: 27 00:09:57 8914MN
Peter.