White to play and Win

[acase]

Hello Andrew:

Here, try out this mate in 16, the only engines I found that find the mate in a reasonable amount of time are The Huntsman 1 (instantly), and SlowChess 2.9 (about 3 minutes)

[pgn][Event "Mate in 16"]
[Site "Columbus, Ohio"]
[Date "2023.06.13"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "17:35:36"]
[TimeControl "0"]
[SetUp "1"]
[FEN "2N5/1KB5/p1NRP1p1/2kn1P1b/P1p1p1r1/8/3p1n2/8 w - - 0 1"]
[Termination "normal"]
[PlyCount "31"]
[WhiteType "program"]
[BlackType "program"]

*
[/pgn]

This position screams Rxd5+. SF 15.1 was misleading me after few moves so I tried Rybka 2.2 (64-bit) from December 2006, which is embedded in Arena 2.0.1 GUI and spotted a checkmate in 14 moves immediately after the first two moves (four plies) from SF 15.1 were played. I cleared hash and tried more times later, always unsuccessful because Rybka 2.2 (64-bit) eventually sees the checkmate, but with more moves played. It can be said that the first Rybka analysis was really lucky. The first 17 plies (9 moves by white and 8 by black) are the only moves with optimal solution, then black can choose between two moves that equally lead to a checkmate in the same number of moves via transposition of moves:

[pgn][Event "Mate in 16"]
[Site ""]
[Date ""]
[Result "1-0"]
[SetUp "1"]
[FEN "2N5/1KB5/p1NRP1p1/2kn1P1b/P1p1p1r1/8/3p1n2/8 w - - 0 1"]
[PlyCount "31"]

1.Rxd5+ Kxd5 2.Nb6+ Kc5 3.Nd7+ Kd5 4.Nf6+ Kc5 5.Bb6+ Kd6 6.Ne8+ Kd5 7.Nc7+ Kd6 8.Ba5 Nd3 9.Ne8+ Kd5 (9...Kc5 10.Bb6+ Kd5 11.Nf6+ {(The same position that in the mainline)}) 10. Nf6+ Kc5 11.Bb6+ Kd6 12.Bc7+ Kc5 13.Nd7+ Kd5 14.Nb6+ Kc5 15.Bd8 d1=Q {(any)} 16.Be7# 1-0[/pgn]

Nice dance of the knights, like the homonym Prokofiev's piece music (Act 1, Scene 2, No. 13 Allegro pesante from Romeo and Juliet by Sergei Sergeyevich Prokofiev).

I would want to know the source of the problem, if possible. Thanks in advance.

Regards from Spain.

Ajedrecista.

Hello Jesus, nice reference to Prokofiev's music there! of course I was familiar with this great piece of music, and I find your reference appropriate of course

[acase]

I would want to know the source of the problem, if possible. Thanks in advance.

Regards from Spain.

Ajedrecista.

Sorry Jesus, I didn't see that part of your post, it was a mate in 16 by Lutz Neweklowsky, and here is another one by him that is a mate in 27 with an amusing Knight dance, if you want the solution then try The Huntsman 1, it solves this instantly:

[pgn][Event "Mate in 27"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "05:40:52"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1"]
[Termination "normal"]
[PlyCount "53"]
[WhiteType "program"]
[BlackType "program"][/pgn]

Lutz releases quite a few mate in x problems regularly here:
https://gameknot.com/chess-puzzles.pl?s ... de&m=0&s=7

[Ajedrecista]

Hello Andrew:

I would want to know the source of the problem, if possible. Thanks in advance.

Regards from Spain.

Ajedrecista.

Sorry Jesus, I didn't see that part of your post, it was a mate in 16 by Lutz Neweklowsky, and here is another one by him that is a mate in 27 with an amusing Knight dance, if you want the solution then try The Huntsman 1, it solves this instantly:

[pgn][Event "Mate in 27"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "05:40:52"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1"]
[Termination "normal"]
[PlyCount "53"]
[WhiteType "program"]
[BlackType "program"][/pgn]

Lutz releases quite a few mate in x problems regularly here:
https://gameknot.com/chess-puzzles.pl?s ... de&m=0&s=7

Thank you for your answer. I found Chest parameters that solved the mate-in-27 position in 0.049 seconds!

Code: Select all

FEN: 8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1

ChestUCI:
FEN: 8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - -   (7+12)
Stellungs-Analyse:  C0/R0/K1/P3/X9   W:7/35
Suche nach Spezial-Matt [C0/R0/K0/P2/X6] in 27 ...  (Hash=64MB)
  27	00:00	           0	0	+M27	Qd4xe3+
Suche abgeschlossen ...  (Zeit=0.05s)
Matt in 27 gefunden !  (1 Lösung in 00:00)
 27/27	00:00	      51.861	1.058.387	+M27	Qd4xe3+ f4xe3 Nc2d4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a5a6 d5d4 Ng1h3+ Kf4f3 Nh3g5+ Kf3f4 Ng5e6+ Kf4f3 Ne6xd4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a2a3 d6d5 a3a4 d5d4 Ng1h3+ Kf4f3 Nh3g5+ Kf3f4 Ng5e6+ Kf4f3 Ne6xd4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a4a5 Rf2f3 Ng1h3+

[pgn][Event "Mate in 27"]
[Site ""]
[Date ""]
[Round "?"]
[Result "1-0"]
[SetUp "1"]
[FEN "8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1"]
[PlyCount "53"]

1.Qxe3+ fxe3 2.Nd4+ Kf4 3.Ne6+ Kf3 4.Ng5+ Kf4 5.Nh3+ Kf3 6.Ng1+ Kf4 7.a6 d4 8.Nh3+ Kf3 9.Ng5+ Kf4 10.Ne6+ Kf3 11.Nxd4+ Kf4 12.Ne6+ Kf3 13.Ng5+ Kf4 14.Nh3+ Kf3 15.Ng1+ Kf4 16.a3 d5 17.a4 d4 18.Nh3+ Kf3 19.Ng5+ Kf4 20.Ne6+ Kf3 21.Nxd4+ Kf4 22.Ne6+ Kf3 23.Ng5+ Kf4 24.Nh3+ Kf3 25.Ng1+ Kf4 26.a5 Rf3 27.Nh3# 1-0[/pgn]

Regards from Spain.

Ajedrecista.

[Chessqueen]

Hello Andrew:

I would want to know the source of the problem, if possible. Thanks in advance.

Regards from Spain.

Ajedrecista.

Sorry Jesus, I didn't see that part of your post, it was a mate in 16 by Lutz Neweklowsky, and here is another one by him that is a mate in 27 with an amusing Knight dance, if you want the solution then try The Huntsman 1, it solves this instantly:

[pgn][Event "Mate in 27"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "05:40:52"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1"]
[Termination "normal"]
[PlyCount "53"]
[WhiteType "program"]
[BlackType "program"][/pgn]

Lutz releases quite a few mate in x problems regularly here:
https://gameknot.com/chess-puzzles.pl?s ... de&m=0&s=7

Thank you for your answer. I found Chest parameters that solved the mate-in-27 position in 0.049 seconds!

Code: Select all

FEN: 8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1

ChestUCI:
FEN: 8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - -   (7+12)
Stellungs-Analyse:  C0/R0/K1/P3/X9   W:7/35
Suche nach Spezial-Matt [C0/R0/K0/P2/X6] in 27 ...  (Hash=64MB)
  27	00:00	           0	0	+M27	Qd4xe3+
Suche abgeschlossen ...  (Zeit=0.05s)
Matt in 27 gefunden !  (1 Lösung in 00:00)
 27/27	00:00	      51.861	1.058.387	+M27	Qd4xe3+ f4xe3 Nc2d4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a5a6 d5d4 Ng1h3+ Kf4f3 Nh3g5+ Kf3f4 Ng5e6+ Kf4f3 Ne6xd4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a2a3 d6d5 a3a4 d5d4 Ng1h3+ Kf4f3 Nh3g5+ Kf3f4 Ng5e6+ Kf4f3 Ne6xd4+ Kf3f4 Nd4e6+ Kf4f3 Ne6g5+ Kf3f4 Ng5h3+ Kf4f3 Nh3g1+ Kf3f4 a4a5 Rf2f3 Ng1h3+

[pgn][Event "Mate in 27"]
[Site ""]
[Date ""]
[Round "?"]
[Result "1-0"]
[SetUp "1"]
[FEN "8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1"]
[PlyCount "53"]

1.Qxe3+ fxe3 2.Nd4+ Kf4 3.Ne6+ Kf3 4.Ng5+ Kf4 5.Nh3+ Kf3 6.Ng1+ Kf4 7.a6 d4 8.Nh3+ Kf3 9.Ng5+ Kf4 10.Ne6+ Kf3 11.Nxd4+ Kf4 12.Ne6+ Kf3 13.Ng5+ Kf4 14.Nh3+ Kf3 15.Ng1+ Kf4 16.a3 d5 17.a4 d4 18.Nh3+ Kf3 19.Ng5+ Kf4 20.Ne6+ Kf3 21.Nxd4+ Kf4 22.Ne6+ Kf3 23.Ng5+ Kf4 24.Nh3+ Kf3 25.Ng1+ Kf4 26.a5 Rf3 27.Nh3# 1-0[/pgn]

Regards from Spain.

Ajedrecista.

Huntman -1 see it instantly

FEN: 8/p7/3p1B1N/P2p4/3Qpp2/4rkp1/P1N1prp1/4Kb2 w - - 0 1

Huntsman:
classical evaluation enabled
1/1 00:00 262 262k -0.61 Qd4xe3+ f4xe3
2/2 00:00 527 527k +0.06 Qd4xe3+ f4xe3
3/3 00:00 754 754k +0.06 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4
4/4 00:00 1k 1,053k +0.06 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4
5/5 00:00 3k 1,651k -0.39 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
6/6 00:00 4k 1,820k -0.39 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
7/6 00:00 5k 2,521k -0.39 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
8/7 00:00 6k 2,759k +0.20 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
9/10 00:00 10k 3,185k +0.02 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3
10/15 00:00 11k 2,761k +0.25 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4
11/15 00:00 14k 2,809k +0.25 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
12/27 00:00 44k 3,636k +0.05 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4
13/28 00:00 48k 3,696k +0.05 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3
14/30 00:00 52k 4,024k +0.05 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4
15/30 00:00 63k 3,966k +0.05 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4
16/37 00:00 77k 3,868k +0.40 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d6-d5 a3-a4 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
17/44 00:00 90k 4,083k +0.50 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3
18/32 00:00 93k 4,046k +0.50 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d6-d5
19/39 00:00 103k 4,106k +0.50 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d6-d5 a3-a4 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3
20/47 00:00 224k 4,232k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
21/41 00:00 246k 4,247k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
22/41 00:00 284k 4,171k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
23/41 00:00 336k 4,152k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d6-d5 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
24/41 00:00 367k 4,172k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
25/41 00:00 437k 4,239k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
26/41 00:00 479k 4,281k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3
27/41 00:00 555k 4,266k 0.00 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3 d6-d5 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4
28/41 00:00 565k 4,246k +M27 Qd4xe3+ f4xe3 Nc2-d4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a5-a6 d5-d4 Ng1-h3+ Kf4-f3 Nh3-g5+ Kf3-f4 Ng5-e6+ Kf4-f3 Ne6xd4+ Kf3-f4 Nd4-e6+ Kf4-f3 Ne6-g5+ Kf3-f4 Ng5-h3+ Kf4-f3 Nh3-g1+ Kf3-f4 a2-a3

[acase]

Huntman -1 see it instantly [/size]

I had already mentioned that The Huntsman 1 solved it instantly when I originally posted the mate in 27.(let me add your favorite emoticon)

Here is a mate in 22 that The Huntsman 1 sees instantly, but most other engines fail at except Crystal:

[pgn][Event "Mate in 22"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "22:54:08"]
[TimeControl "0"]
[SetUp "1"]
[FEN "1B3N2/5p1B/2K2pn1/5krb/4p1p1/4P1P1/2P1PP2/8 w - - 0 1"]
[Termination "normal"]
[PlyCount "43"]
[WhiteType "program"]
[BlackType "program"][/pgn]

[Ajedrecista]

Hello Andrew:

[...]

Here is a mate in 22 that The Huntsman 1 sees instantly, but most other engines fail at except Crystal:

[pgn][Event "Mate in 22"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "22:54:08"]
[TimeControl "0"]
[SetUp "1"]
[FEN "1B3N2/5p1B/2K2pn1/5krb/4p1p1/4P1P1/2P1PP2/8 w - - 0 1"]
[Termination "normal"]
[PlyCount "43"]
[WhiteType "program"]
[BlackType "program"][/pgn]

An absolute beauty from the 70s! Other one unknown for me, this time easily found at YACPDB and PDB. The problem is in Chest database and the solution was found in 0.011 seconds with the specified parameters.

[pgn][Event "Mate in 22"]
[Site ""]
[Date ""]
[Result "1-0"]
[SetUp "1"]
[FEN "1B3N2/5p1B/2K2pn1/5krb/4p1p1/4P1P1/2P1PP2/8 w - - 0 1"]
[PlyCount "43"]

1.Ba7 Ke5 2.Bd4+ Kf5 3.Bc5 Ke5 4.Bd6+ Kf5 5.Ba3 Ke5 6.Bb2+ Kf5 7.c3 Ke5 8.c4+ Kf5 9.Ba3 Ke5 10.Bd6+ Kf5 11.Bc5 Ke5 12.Bd4+ Kf5 13.Ba7 Ke5 14.Bb8+ Kf5 15.Kc7 Ke5 16.Kd7+ Kf5 17.Ne6 fxe6 18.Bf4 e5 19.Kd6 exf4 20.exf4 e3 21.Kd5 exf2 22.e4# 1-0[/pgn]

A booklet by the author of this problem (found via EG magazine) gathers some Latvian composers and problems; this #22 problem is reprinted as No. 99037 at page 29. It got the First Prize, but it was not the only First Prize for Dulbergs. Well done!

Regards from Spain.

Ajedrecista.

[acase]

Hello Andrew:

[...]

Here is a mate in 22 that The Huntsman 1 sees instantly, but most other engines fail at except Crystal:

[pgn][Event "Mate in 22"]
[Site "Columbus, Ohio"]
[Date "2023.06.15"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "22:54:08"]
[TimeControl "0"]
[SetUp "1"]
[FEN "1B3N2/5p1B/2K2pn1/5krb/4p1p1/4P1P1/2P1PP2/8 w - - 0 1"]
[Termination "normal"]
[PlyCount "43"]
[WhiteType "program"]
[BlackType "program"][/pgn]

An absolute beauty from the 70s! Other one unknown for me, this time easily found at YACPDB and PDB. The problem is in Chest database and the solution was found in 0.011 seconds with the specified parameters.

[pgn][Event "Mate in 22"]
[Site ""]
[Date ""]
[Result "1-0"]
[SetUp "1"]
[FEN "1B3N2/5p1B/2K2pn1/5krb/4p1p1/4P1P1/2P1PP2/8 w - - 0 1"]
[PlyCount "43"]

1.Ba7 Ke5 2.Bd4+ Kf5 3.Bc5 Ke5 4.Bd6+ Kf5 5.Ba3 Ke5 6.Bb2+ Kf5 7.c3 Ke5 8.c4+ Kf5 9.Ba3 Ke5 10.Bd6+ Kf5 11.Bc5 Ke5 12.Bd4+ Kf5 13.Ba7 Ke5 14.Bb8+ Kf5 15.Kc7 Ke5 16.Kd7+ Kf5 17.Ne6 fxe6 18.Bf4 e5 19.Kd6 exf4 20.exf4 e3 21.Kd5 exf2 22.e4# 1-0[/pgn]

A booklet by the author of this problem (found via EG magazine) gathers some Latvian composers and problems; this #22 problem is reprinted as No. 99037 at page 29. It got the First Prize, but it was not the only First Prize for Dulbergs. Well done!

Regards from Spain.

Ajedrecista.

Jesus, Here's a nice mate in 17. Crystal seems to get this one reasonably fast, but The Huntsman 1 and all other engines I tried struggle with it.:

[pgn][Event "Mate in 17"]
[Site "Columbus, Ohio"]
[Date "2023.06.16"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "20:30:26"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1"]
[Termination "normal"]
[PlyCount "33"]
[WhiteType "program"]
[BlackType "program"][/pgn]

[Ajedrecista]

Hello Andrew:

Jesus, Here's a nice mate in 17. Crystal seems to get this one reasonably fast, but The Huntsman 1 and all other engines I tried struggle with it.:

[pgn][Event "Mate in 17"]
[Site "Columbus, Ohio"]
[Date "2023.06.16"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "20:30:26"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1"]
[Termination "normal"]
[PlyCount "33"]
[WhiteType "program"]
[BlackType "program"][/pgn]

Other great one! This one is from 2022 and with lots of notes at PDB. This was solved by AnMon 5.60 (from December, 2006), which is one of the engines embedded at Arena 2.0.1 GUI:

Code: Select all

FEN: 8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1

AnMon 5.60:
   1+	00:00	           1	0	+5,05	Rc4xc5
   1	00:00	           3	0	+5,10	Rc4xc5
   2	00:00	          44	0	 0,00	Rc4xc5
   2+	00:00	          54	0	+4,41	Bg6f7 Kb2b1+ Kg7g6
   2	00:00	          63	0	+4,41	Bg6f7 Kb2b1+ Kg7g6
   3	00:00	       1.021	0	+2,64	Bg6f7 Kb2b1+ Kg7g6 Ba1d4
   3+	00:00	       1.044	0	+2,79	Rc4e4 Kb2c2+ Kg7h6
   3	00:00	       1.137	0	+3,07	Rc4e4 Kb2c1+ Kg7f8
   3+	00:00	       1.145	0	+3,19	Rc4f4 Kb2c3 Ra4xa3
   3	00:00	       1.161	0	+3,23	Rc4f4 Kb2c1+ Kg7f8
   4	00:00	       2.828	0	+3,01	Rc4f4 Kb2c1+ Kg7f7 Ba1b2 Rf4c4+ Kc1d2
   5	00:00	       5.920	0	+3,14	Rc4f4 Kb2c1+ Kg7f7 Ba1d4 Ra4xa3
   6	00:00	      19.832	0	+3,03	Rc4f4 Kb2c1+ Kg7f7 Ba1d4 Ra4xa3 Kc1d2
   6+	00:00	      27.903	0	+3,04	Rc4g4 Kb2c3 Kg7f7 c5c4
   6	00:00	      29.642	0	+3,09	Rc4g4 Kb2c1+ Kg7f7 Ba1d4 Ra4xa3 Kc1d1
   7	00:00	      88.304	0	+2,21	Rc4g4 Kb2c1+ Kg7f8 Ba1g7+ Kf8xe7 Bg7f6+ Ke7d6 Bf6e5+ Kd6xe5 a2a1Q+ Ke5d6 Kc1d2 Rg4g2+ Kd2e3 Rg2g3+ Ke3f2
   7+	00:00	      88.879	0	+2,43	Rc4f4 c5c4 Ra4xc4 c6c5
   7	00:00	      96.745	0	+2,72	Rc4f4 Kb2c1+ Kg7g8 Ba1d4 Ra4xa3 Kc1b2 Bg6d3
   7+	00:00	     124.902	0	+2,73	Rc4h4 Kb2c1+ Kg7f7 Ba1b2 Ra4c4+ Kc1d2 Rh4h2+ Kd2e3 Rc4e4+ Ke3d3 Rh2h3+ Kd3c2
   7	00:00	     143.134	0	+3,07	Rc4h4 Kb2c1+ Kg7f7 Ba1f6 Rh4h1+ Kc1d2 Rh1h2+ Kd2e1 Ra4xa3
   8	00:00	     283.452	0	+2,77	Rc4h4 Kb2c1+ Kg7f7 Ba1f6 Rh4h1+ Kc1d2 Ra4xa3 c5c4 Ra3xa2+ b3xa2 Rh1h2+ Kd2d1 Rh2xa2
   9	00:01	   1.571.511	704.145	+3,39	Rc4h4 Kb2c3 Ra4a7 Kc3d2+ Kg7f7 Ba1b2 Rh4h2+ Kd2d1 Rh2h1+ Kd1d2 Ra7d7+ Kd2e2 Bg6h5+ Ke2e3 Rh1e1+ Ke3f2 Re1e2+ Kf2g3
  10	00:02	   2.950.055	704.145	+3,38	Rc4h4 Kb2c1+ Kg7f7 Ba1e5 Ra4xa3 Kc1b2 Rh4a4 Be5f6 Ra3xa2+ b3xa2 Bg6d3 a2a1Q Ra4xa1
  10+	00:02	   3.679.815	704.145	+3,39	Rc4g4 Kb2c1+ Kg7f7 Ba1d4 Ra4xa3 Kc1b2 Ra3a7 Kb2c1 Rg4g2 a2a1B
  10	00:02	   4.077.884	704.145	+3,64	Rc4g4 Kb2c1+ Kg7g8 Ba1d4 Rg4g1+ Bd4xg1 Ra4xa3 Kc1d1 Kg8f7 b3b2 Ra3xa2 b2b1Q Bg6xb1
  11-	00:04	   5.919.688	1.409.050	+3,63	Rc4g4 Kb2c1+ Kg7g8 Ba1d4 Ra4xa3 Kc1b2 Ra3a4 Bd4f6 Rg4g2+ Kb2c3 Rg2g3+ Kc3d2 Rg3d3+ Kd2c2 Rd3e3+ Kc2b2 Re3e2+ Kb2c1 Ra4c4+ Kc1d1 Rc4xc5
  11-	00:05	   7.376.472	1.434.954	+3,61	Rc4g4 Kb2c1+ Kg7g8 Ba1d4 Ra4xa3 Kc1b2 Ra3a4 Bd4f6 Bg6h5 Kb2c3 Kg8f7 Kc3d3 Rg4g3+ Kd3c2 Bh5g6+ Kc2b2 Kf7e8 c5c4 Rg3g2+ Kb2c3 Rg2xa2 b3xa2 Ra4xa2
  11	00:06	   9.037.464	1.434.954	+3,28	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Rg4g1+ Kc1d2 Ra4xa3 Bf6d4 Ra3xa2+ b3xa2 Rg1g2+ Kd2e1 Rg2xa2 Bd4f6 Kf7e8
  11+	00:06	   9.117.462	1.434.954	+3,29	Rc4h4 Kb2c1+ Kg7f7 Ba1e5 Ra4xa3 Kc1d1 Rh4h1+ Kd1e2 Kf7xe7 Be5d6+ Ke7xd6 a2a1Q
  11	00:07	  10.525.892	1.516.759	+3,52	Rc4h4 Kb2c1+ Kg7f7 Ba1e5 Rh4h1+ Kc1b2 Ra4g4 c5c4 Rg4g2+ Kb2c3 Kf7f8 Be5d6 Rh1c1+ Kc3d4 Kf8g8 a2a1Q Rg2g4+ Kd4e3 Rg4e4+ Ke3d3 Rc1xa1
  12+	00:10	  15.678.603	1.407.063	+3,53	Rc4h4 Kb2c1+ Kg7f7 Ba1e5 Rh4h1+ Kc1d2 Ra4xa3 Kd2c3 Rh1h3+ Kc3d4 Kf7xe7 a2a1R Rh3h4+ Kd4d5 Bg6e4+ Kd5c4 Be4xc6+ Be5d4
  12	00:15	  21.573.581	1.408.724	+3,70	Rc4h4 Kb2c1+ Kg7f7 Ba1f6 Ra4b4 a2a1Q Rb4xb3 Bf6xh4 Rb3b1+ Kc1d2 Rb1xa1 Kd2e3 Ra1xa3+ Ke3e2
  12+	00:25	  37.952.729	1.622.759	+M18	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Rc1xc5 Kb2b1 Bg8h7+ Kb1b2 Rc5f5 Kb2b1 Rf5f4+ Kb1b2
  12+	00:26	  37.953.840	1.622.759	+M17	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Bg8f7 c5c4 Rc1xc4 Kb2b1 Bf7g6+ Kb1b2 Bg6c2 b3xc2
  12	00:26	  38.438.834	1.622.759	+M17	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Bg8f7 c5c4 Rc1xc4 Kb2b1 Bf7g6+ Kb1b2 Bg6c2 b3xc2

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

Hermann 2.4 (64-bit) from November, 2008 is other engine embedded at Arena 2.0.1 GUI that solves the problem:

Code: Select all

FEN: 8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1

Hermann 2.4 64 bit:
  1/4	00:00	          55	55.000	+4,54	Rc4xc5
 11/26	00:01	   1.142.467	1.215.390	+4,37	Rc4h4 Kb2c1+ Kg7f7 Ba1e5 Ra4xa3 Kc1b2 Rh4a4 Be5d6 Ra4a7 c5c4 Ra3a4
 11/27+	00:01	   1.621.867	1.226.828	+4,37	Rc4g4 Kb2c1+ Kg7f7 Ba1e5 Ra4xa3 Kc1b2 Ra3a7 c5c4 Rg4xc4 c6c5
 11/27	00:01	   1.794.895	1.216.878	+4,72	Rc4g4 Kb2c1+ Kg7f7 Ba1d4 Ra4xa3 a2a1Q Rg4g1+ Kc1d2 Rg1xa1 Bd4xa1 Ra3xa1 b3b2
 12/27	00:02	   2.330.245	1.214.935	+4,63	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Ra4xa3 Kc1b2 Ra3a4 c5c4 Rg4g2+ Kb2c3 Rg2g3+ Kc3d4 Ra4a5
 13/31	00:03	   4.068.790	1.212.754	+4,76	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Rg4g1+ Kc1d2 Ra4xa3 c5c4 Rg1g2+ Kd2c1 Kf7e8 Bf6d4 Rg2h2 Kc1d1
 14/34	00:08	   9.610.186	1.209.285	+4,51	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Rg4g1+ Kc1b2 Ra4c4 a2a1N Rg1g2+ Na1c2 Bg6xc2 b3xc2 Rc4xc5 Bf6c3 Kf7xe7 a3a2 Rg2g1 c2c1Q Rg1xc1 Kb2xc1 Rc5xc3+ Kc1b2
 15/36	00:13	  16.555.705	1.211.364	+4,59	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Ra4xa3 Kc1b2 Ra3a4 c5c4 Rg4g2+ Kb2c3 Rg2g1 c6c5 Rg1c1+ Kc3b2 Rc1d1
 16/40	00:28	  33.345.919	1.197.684	+5,31	Rc4g4 Kb2c1+ Kg7f7 Ba1e5 Rg4g1+ Kc1b2 Ra4c4 a2a1N Kf7xe7 a3a2 Ke7d7 Be5f6 Rc4c1 Na1c2 Bg6xc2 Bf6d4 e6e7 Bd4xg1 Rc1xg1
 17/42	00:50	  59.182.086	1.188.753	+5,59	Rc4g4 Kb2c1+ Kg7f7 Ba1f6 Ra4xa3 Kc1d1 Ra3xb3 a2a1Q Rg4g1+ Kd1e2 Rg1xa1 Bf6xa1 Bg6h5+ Ke2d2 Bh5e2
 17/42+	00:55	  65.568.556	1.194.436	+M17	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Bg8f7 c5c4 Rc1xc4 Kb2b1 Bf7g6+ Kb1b2 Bg6c2 b3xc2 Rc4xb4+
 17/42	00:55	  66.011.363	1.194.841	+M17	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Bg8f7 c5c4 Rc1xc4 Kb2b1 Bf7g6+ Kb1b2 Bg6c2 b3xc2 Rc4xb4+

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

Chest 5.2 also found the checkmate in 17 moves with [C0/R0/K8/P2/X0] parameters:

Code: Select all

FEN: 8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1

ChestUCI:
FEN: 8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - -   (5+8)
Stellungs-Analyse:  C0/R0/K0/P0/X0   W:4/31
Suche nach Spezial-Matt [C0/R0/K8/P2/X0] in 17 ...  (Hash=512MB)
  17	03:44	 136.138.359	612.022	+M17	Ra4b4
Suche abgeschlossen ...  (Zeit=224.67s)
Matt in 17 gefunden !  (1 Lösung in 03:44)
 17/17	03:44	 137.644.249	612.650	+M17	Ra4b4 c5xb4 Bg6h7 c6c5 Kg7g6 Kb2b1 Kg6g5+ Kb1b2 Kg5f5 Kb2b1 Kf5f4+ Kb1b2 Kf4e4 Kb2b1 Ke4e3+ Kb1b2 Ke3d3 Kb2b1 Kd3d2+ Kb1b2 Bh7g8 Kb2b1 Rc4c1+ Kb1b2 Bg8f7 c5c4 Rc1xc4 Kb2b1 Bf7g6+ Kb1b2 Bg6c2 b3xc2 Rc4xb4+

[pgn][Event "Mate in 17"]
[Site ""]
[Date ""]
[Result "1-0"]
[SetUp "1"]
[FEN "8/4p1K1/2p1P1B1/2p5/R1R5/pp6/pk6/b7 w - - 0 1"]
[PlyCount "33"]

1.Rab4 cxb4 2.Bh7 c5 3.Kg6 Kb1 4.Kg5+ Kb2 5.Kf5 Kb1 6.Kf4+ Kb2 7.Ke4 Kb1 8.Ke3+ Kb2 9.Kd3 Kb1 10.Kd2+ Kb2 11.Bg8 Kb1 12.Rc1+ Kb2 13.Bf7 c4 14.Rxc4 Kb1 15.Bg6+ Kb2 16.Bc2 bxc2 17.Rxb4 1-0[/pgn]

Regards from Spain.

Ajedrecista.

[Ignacio]

Chest with P1/X1 needs 0.01 sec for mate in 17.

[Eelco de Groot]

Trying some variation on this but it is not so easy to find something that is not immediately Mate in three for White or on the other hand just 0.00. I am just trying the engine, not looking for the solution myself. Am not good at problems.

Maybe this one was not so bad, White has to sacrfice two pieces for the fastest Mate and Black does a minorpromotion to live a few plies longer, so Rybka would not be able to find the best defence. Mate in 15 moves, computer finds it easy..


[fen]8/6K1/1Np3B1/BpP5/1PRP4/pp6/pk6/b7 w - -[/fen]