8 hard positions from the Chest database

Discussion of anything and everything relating to chess playing software and machines.

Moderators: hgm, Rebel, chrisw

Dann Corbit
Posts: 12541
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

8 hard positions from the Chest database

Post by Dann Corbit »

These are the only 8 positions for which I have not found a checkmate solution:
[d]2r1b1Q1/6p1/2P5/5P2/1p2K3/pPp5/n2P4/1B2k3 w - - acd 44; bm Kf4; ce 630; c2 "#23;"; pm Kf4; pv Kf4; id "ChestDB.06301";
[d]8/p1p3Pr/p1p2P2/7p/7k/6p1/p1p3P1/rbK5 w - - acd 100; bm f7; ce 15265; c0 "1.c Sachove Umenie#4048; 1974; Pivovar=S; (+0630.38c1h4); 1-0"; c2 "#64;"; c5 "Pivovar=S; 1-0"; c7 "1.c Sachove Umenie#4048;1974;W:Pivovar=S;(+0630.38c1h4);1-0;1974"; c8 "pv f7 Rxg7 f8=Q Rg5 Qf4+ Rg4 Qf6+ Rg5 Qe7 a5 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c5 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c4 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c3 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a4 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a3 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c6 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c5 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c4 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a6 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a5 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a4 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 Kg4 Qe4# 1-0"; c9 "HHdbVI.0963590.001a.47401"; pm f7; pv f7 Rxg7 f8Q Rg5 Qe7 a5 Qf8 Rg4 Qf6+ Rg5 Qe7 a4 Qe4+ Rg4 Qe5 Rg6 Qf4+ Rg4 Qf6+ Rg5 Qe7 a5 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a3 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c5 Qe6 Rg7 Qf5 Rg4 Qf6+ Rg5 Qe7 c6 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 c4 Qe4+ Rg4 Qe5 Rg6 Qf5 Rg7 Qf6+ Rg5 Qe7 c3 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qf6+ Rg5 Qe7 a4 Qf6 Kg4 Qf3+ Kh4 Qf4+ Rg4 Qe5 Rg8 Qf6+ Rg5 Qe7 c5 Qe6 Rg7 Qf6+ Kg4 Qxg7+ Kf4; id "ChestDB.06531";
[d]qnb5/rp1p4/pPpP4/P1P5/2P5/6K1/8/6Nk w - - acd 207; bm Kf2; ce 10122; c0 "tb04 {m}; 1891; Amelung F; White wins;"; c2 "#49;"; c6 "Arves.38054"; c7 "No. 295582 (id: P1298591) Amelung, Friedrich source 1: Baltische Schachbl atter, No. 135, 1891 stipulation: #55 solution: 1.Kf2 Kh2 2.Se2 Kh1 3.Sf4 Kh2 4.Kf3 Kh1! 5.Ke2 Kg1 6.Ke1 Kh1 7.Kf1 Kh2 8.Kf2 Kh1 9.Se2 Kh2 10.Sg3 Kh3 11.Sf1 dedication: Gewidmet dem Riga'schen Schachverein"; c8 "pv Kf2 Kh2 Ne2 Kh1 Nf4 Kh2 Kf3 Kh1 Ke2 Kg1 Ke1 Kh1 Kf1 Kh2 Kf2 Kh1 Ne2 Kh2 Ng3 Kh3 Nf1 Kg4 Ke3 Kf5 Nh2 Ke5 Ng4+ Kf5 Kf3 Kg5 Ne3 Kh4 Kg2 Kh5 Kh3 Kg5 Kg3 Kh5 Nf5 Kg5 Nh4 Kh5 Nf3 Kg6 Kf4 Kf6 Ne5 Ke6 Ng4 Kf7 Kf5 Kg7 Ne5 Kh6 Kg4 Kh7 Kh5 Kg7 Kg5 Kh7 Nf7 Kg7 Nh6 Kh7 Nf5 Kg8 Kg6 Kh8 Kf6 Kh7 Kg5 Kh8 Kg6 Kg8 Nh6+ Kh8 Kf6 Kh7 Nf7 Kg8 Kg6 Kf8 Nh6 Ke8 Kg7 Kd8 Nf5 Ke8 Ne7 Kd8 Kg8 Ke8 Nxc8 Kd8 Nxa7 Ke8 Kg7 Kd8 Kf7 Qxa7 bxa7 Kc8 a8=Q b5 axb6 a5 b7+ Kd8 Qxb8# 1-0"; c9 "HHdbVI.1655456.001a.89815"; pm Kf2; pv Kf2; id "ChestDB.06505";
[d]8/Pk2p1pp/1Pp1P3/1pP3p1/2p5/2Pp4/3P1P1P/7K w - - acd 82; bm Kg2; ce 348; c2 "#69;"; pm Kg2; pv Kg2; id "ChestDB.06542";
[d]Q1b4q/2Pp2p1/3P1k1b/6pP/3p1pPp/3P1pBK/5P2/8 w - - acd 55; bm Qe4; ce 1057; c0 "td27 {m}; 1938; Blathy O; White wins;"; c2 "#125;"; c5 "Blathy=O; 1-0"; c6 "Arves.34944"; c7 "No. 285539 (id: P1201849) Blathy, Otto Titusz source 1: Festgr u se, 01/1938 source 2: Die Schwalbe, No. 5076, 01/1938 stipulation: #125 dedication: Weihnachts- und Neujahrswunsch"; c9 "HHdbVI.1424761.001a.74312"; pm Qe4; pv Qe4; id "ChestDB.06570";
[d]6B1/k5b1/6N1/p3pBpP/Pp1pPp1p/1P1P1P1P/7K/r7 w - - acd 81; bm Bc4; ce 574; c0 "Chable, Yves; #119"; c2 "#119;"; pm Bc4; pv Bc4 Kb6 Bg4 Kc5 Ne7 Bf6 Nf5 Ra2+ Kg1 Ra1+ Kf2 Ra2+ Ke1 Ra1+ Kd2 Ra2+ Kc1 Rg2 h6 Rh2 Kd1 Bh8 Ne7 Bf6 Ng8 Bh8 h7 Kd6 Nh6 Rh1+ Ke2 Ke7 Nf7 Bf6 h8Q Bxh8 Nxh8 Rh2+ Kf1 Rh1+ Kg2 Ra1; id "ChestDB.06565";
[d]R1n4k/n1p5/pb1p1N1P/3P3p/7p/p1p1P3/P1P1PP1P/7K w - - acd 48; bm Kg2; ce 910; c2 "#34;"; c7 "No. 309494 (id: P1402334) Rotenberg, Jacques; Loustau, Jean-Marc source 1: Phenix, 1993-1994 stipulation: #34 solution: 1.Tb8! h3 2.Kg1 Lc5 3.Kf1 Lb6 4.Ke1 Lc5 5.Kd1 Lb6 6.Kc1 Lc5 7.Kb1 Lb6 8.Ka1 h4 9.Kb1 Lc5 10.Kc1 Lb6 11.Kd1 Lc5 12.Ke1 Lb6 13.Kf1 Lc5 14.Kg1 Lb6 15.Kh1 a5 16.Kg1 Lc5 17.Kf1 Lb6 18.Ke1 Lc5 19.Kd1 Lb6 20.Kc1 Lc5 21.Kb1 Lb6 22.Ka1 a4 23.Kb1 Lc5 24.Kc1 Lb6 25.Kd1 Lc5 26.Ke1 Lb6 27.Kf1 Lc5 28.Kg1 Lb6 29.Kh1 Lc5! 30.Tb1 Ld4 31.exd4 Se7 32.Tg1 Sg6 33.Txg6 ...34.Tg8#"; pm Kg2; pv Kg2; id "ChestDB.06430";
[d]qrr1b3/pn2p3/npppp1P1/4pP2/2P2BPp/PPN1P2B/4R2K/2k5 w - - acd 57; bm Bg5; ce 1039; c0 "Na2+ an Bg5 both win easily"; c2 "#20;"; pm Bg5; pv Bg5 e4 Nxe4 Nbc5 Nc3 Ne4 Nxe4 Nb4 axb4 c5 Nc3 Qe4 Nxe4 cxb4 Bxe7 d5 Re1+ Kc2 cxd5 exf5 gxf5 Kxb3 Bg4 Kb2 g7 Bf7 Bf6+ Kb3 d6 Rc2+ Kh3; id "ChestDB.06214";
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.
Jouni
Posts: 3291
Joined: Wed Mar 08, 2006 8:15 pm

Re: 8 hard positions from the Chest database

Post by Jouni »

Really? You have solved all 100-126 movers :o ..
Jouni
Dann Corbit
Posts: 12541
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: 8 hard positions from the Chest database

Post by Dann Corbit »

Probably not.
I have these solved:
n7/b1p1K3/1pP4p/1P4p1/6p1/1p4Pn/1P2N1br/3NRn1k w - -
8/4p3/3p4/p5p1/3n2Kp/p3N1p1/rb1N2pr/k1n3Rb w - -
8/1p1p4/3p2p1/5pP1/1p3P1k/1P1p1P1p/1P1P1P1K/7B w - -
n7/pPp5/p4p2/5p2/p6p/p6K/3rb3/n6k w - -

but I guess that the file I was looking at (from the "Best test Suite for mate finding" thread) probably has some missing.
Those that I posted are those not solved from the set posted in the best test suite thread.
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.
acase
Posts: 983
Joined: Wed Mar 15, 2006 1:14 am
Location: Columbus, Ohio USA
Full name: Andrew R Case

Re: 8 hard positions from the Chest database

Post by acase »

Hi Dann, here is what I have on this one (mate in 69):

[pgn][Event "Mate in 69"]
[Site "Columbus, Ohio"]
[Date "2024.03.29"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "17:15:07"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/Pk2p1pp/1Pp1P3/1pP3p1/2p5/2Pp4/3P1P1P/7K w - - 0 1"]
[Termination "normal"]
[PlyCount "137"]
[WhiteType "human"]
[BlackType "human"]

1. Kg2 g4 {Black MUST play 1...g4, or 2...g4, otherwise the mate is
shorter than 69 moves} (1. .. Ka8 2. Kf1 Kb7? 3. f3! Ka8 4. Kf2 Kb7 5. Ke1
Ka8 6. Kd1 Kb7 7. Kc1 Ka8 8. Kb2 Kb7 9. Ka3 Ka8 10. Kb4 Kb7 11. Ka5 h6 12.
Kb4 Ka8 13. Ka3 Kb7 14. Ka2 Ka8 15. Kb2 Kb7 16. Ka3 h5 17. h3 Ka8 18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24. Ka3 Ka8 25. Kb4 Kb7 26. Ka5 h4 27. Kb4 Ka8 28. Ka3
Kb7 29. Ka2 Ka8 30. Kb2 Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 g4 34. fxg4 g5
35. Kb4 Ka8 36. Ka3 Kb7 37. Kb2 Ka8 38. Kb1 Kb7 39. Kc1 b4 40. cxb4 c3 41.
dxc3 Ka8 42. b5 d2+ 43. Kxd2 cxb5 44. c6 b4 45. c4 b3 46. c7 Kb7 47. a8=Q+
Kxb6 48. c8=Q b2 49. Qcc6#) 2. Kf1 Ka8 3. Ke1 Kb7 4. Kd1 Ka8 5. Kc1 Kb7 6.
Kb2 Ka8 7. Ka3 Kb7 8. Ka2 Ka8 9. Kb2 Kb7 10. Ka3 Ka8 11. Kb4
Kb7 12. Ka5 h6 13. Kb4 Ka8 14. Ka3 Kb7 15. Ka2 Ka8 16. Kb2 Kb7 17. Ka3 Ka8
18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24.
Ka3 Ka8 25. Kb4 Kb7 26. Ka5 g5 27. Kb4 Ka8 28. Ka3 Kb7 29. Ka2 Ka8 30. Kb2
Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 h5 34. Kb4 Ka8 35. Ka3 Kb7 36. Ka2 Ka8
37. Kb2 Kb7 38. Ka3 Ka8 39. Kb4 Kb7 40. Ka5 h4 41. Kb4 Ka8 42. Ka3 Kb7 43.
Ka2 Ka8 44. Kb2 Kb7 45. Ka3 Ka8 46. Kb4 Kb7 47. Ka5 h3 48. Kb4 Ka8 49. Ka3
Kb7 50. Ka2 Ka8 51. Kb2 Kb7 52. Ka3 Ka8 53. Kb4 Kb7 54. Ka5 g3 55. fxg3 g4
56. Kb4 Ka8 57. Ka3 Kb7 58. Ka2 Ka8 59. Kb2 Kb7 60. Ka3 Ka8 61. Kb4 Kb7 62.
Ka5 b4 63. Kxb4 Ka8 64. Ka5 Kb7 65. a8=Q+ Kxa8 66. Ka6 Kb8 67. b7 Kc7 68.
Ka7 Kd8 69. b8=Q# 1-0
[/pgn]

If I am wrong or perhaps you or someone else can refine it further, then please post. I think my pgn gives the gist of how this one works though.
acase
Posts: 983
Joined: Wed Mar 15, 2006 1:14 am
Location: Columbus, Ohio USA
Full name: Andrew R Case

Re: 8 hard positions from the Chest database

Post by acase »

I think that me and Herbert (Paloma) worked this one out to be a mate in 23:

[pgn][Event "Mate in 23?"]
[Site "Columbus, Ohio"]
[Date "2024.03.07"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "09:19:50"]
[TimeControl "0"]
[SetUp "1"]
[FEN "R1n4k/n1p5/pb1p1N1P/3P3p/7p/p1p1P3/P1P1PP1P/7K w - - 0 1"]
[Termination "normal"]
[PlyCount "9"]
[WhiteType "program"]
[BlackType "program"]

1. Rb8 h3 2. Kg1 a5 3. Kh1 a4 4. Kg1 Bc5 5. Kh1? (5. Rb1! Nb6 6. Kh1 Nd7 7. Nxd7 Kh7 8. Nxc5 Kxh6 9. Ne6 Nc8 (9. ..
Kg6 10. Rb8 c6 11. Ra8 cxd5 12. Rxa7 d4 13.
Nxd4 Kf6 14. f4 Kg6 15. e4 h4 16. Kg1 Kf6 17. Kf2 Kg6 18. Kf3 Kf6 19. Kg4
Kg6 20. Ne6 d5 21. Nf8+ Kf6 22. e5#) (9. .. c6 10. Rb7 Nc8 11. Rg7 cxd5 12. f4 Ne7 13. Rxe7 Kg6 14. Nd4 Kf6 15. Rd7
Kg6 16. f5+ Kf6 17. Kg1 h4 18. Kf2 Kg5 19. Kf3 Kf6 20. Kg4 Ke5 21. Kg5 Ke4
22. Re7#) 10. Rg1 Ne7 (10. .. Nb6 11. Nf8
h4 12. e4 Kh5 13. f4 Nc4 14. Rg6 Ne5 15. Rg7 Ng4 16. Rg5+ Kh6 17. Rxg4 Kh5
18. Rg6 c6 19. f5 cxd5 20. Ne6 dxe4 21. Nf4#) 11. Nf8 h4 12. e4 c6 13. dxc6 Nxc6 14. Rg6+ Kh5 15. f4 Ne5 16. Rg7 d5
17. fxe5 Kh6 18. Rg1 Kh5 19. e6 Kh6 20. e7 d4 21. e8=Q d3 22. Qg6#) 1-0[/pgn]

Once again if you or anyone else see anything I'm missing or could refine it any more than please post it.
Dann Corbit
Posts: 12541
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: 8 hard positions from the Chest database

Post by Dann Corbit »

Thanks for the assistance
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.
acase
Posts: 983
Joined: Wed Mar 15, 2006 1:14 am
Location: Columbus, Ohio USA
Full name: Andrew R Case

Re: 8 hard positions from the Chest database

Post by acase »

Dann Corbit wrote: Fri Mar 29, 2024 11:55 pm Thanks for the assistance
I did accidentally post the wrong pgn for the mate in 23 though, so here it is:

[pgn][Event "Mate in 23"]
[Site "Columbus, Ohio"]
[Date "2024.02.28"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "22:51:45"]
[TimeControl "0"]
[SetUp "1"]
[FEN "R1n4k/n1p5/pb1p1N1P/3P3p/7p/p1p1P3/P1P1PP1P/7K w - - 0 1"]
[Termination "normal"]
[PlyCount "45"]
[WhiteType "human"]
[BlackType "human"]

1. Rb8 {+M23/119 1} h3 2. Kg1 Bc5 (2. .. h4 3. Kh1 {+M21/81 1} a5 4. Kg1
Bc5 5. Rb1 Nb6 6. Kh1 Nd7 7. Nxd7 Kh7 8. Nxc5 Kxh6 (8. .. Nc8 9. Nd7
{+M14/65 120} Kxh6 10. Rg1 Ne7 11. Nf6 Nf5 12. Rg4 a4 13. e4 Ne7 14. f4 c6
15. Ng8+ Nxg8 16. Rxg8 cxd5 17. f5 dxe4 18. Rg1 Kh5 19. f6 d5 20. f7 e3 21.
f8=Q d4 22. Qh8#) 9. Rb7 Nc8 10. Rxc7 Nb6 11. Rc6) (2. .. a5 3. Kh1
{+M21/73 1} h4 4. Kg1 Bc5 5. Rb1 Nb6 6. Kh1 Nd7 7. Nxd7 Kh7 8. Nxc5 Kxh6 9.
Rb7 Nc8 10. Rxc7 Nb6 11. e4 Kg5 12. Rc6 Na4 13. Nxa4 Kf4 14. Rxd6 Kxe4 15.
Nxc3+ Kf5 16. Rc6 Ke5 17. e4 a4 18. Kg1 Kd4 19. d6 Ke5 20. d7 Kf4 21. d8=Q
Kg4 22. Qd7+ Kf4 23. Qf5#) 3. Rb1! Nb6 4. Kh1 Nd7 5. Nxd7 Kh7 6. Nxc5 dxc5
7. d6! cxd6 8. Rb7+ Kxh6 9. Rxa7 d5 (9. .. Kg5 10. Rxa6 {+M14/64 4} d5 11.
Rxa3 Kf5 12. Rb3 d4 13. exd4 Ke6 14. a4 cxd4 15. Kg1 Kd6 16. a5 d3 17. exd3
Kc6 18. a6 Kc5 19. a7 Kd4 20. a8=Q h4 21. Qc6 Ke5 22. Rb5+ Kd4 23. Qc4#)
10. Rxa6+ Kg5 11. Rxa3 Kf5 12. Rb3 d4 13. exd4 cxd4 14. Kg1 Ke6 15. a4 h4
16. a5 Kd7 17. a6 d3 18. exd3 Kd6 19. a7 Kc7 20. a8=Q Kd7 21. Qa6 Ke7 22.
Rb7+ Kd8 23. Qa8# 1-0
[/pgn]
Paloma
Posts: 1167
Joined: Thu Dec 25, 2008 9:07 pm
Full name: Herbert L

Re: 8 hard positions from the Chest database

Post by Paloma »

acase wrote: Fri Mar 29, 2024 11:41 pm Hi Dann, here is what I have on this one (mate in 69):

[pgn][Event "Mate in 69"]
[Site "Columbus, Ohio"]
[Date "2024.03.29"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "17:15:07"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/Pk2p1pp/1Pp1P3/1pP3p1/2p5/2Pp4/3P1P1P/7K w - - 0 1"]
[Termination "normal"]
[PlyCount "137"]
[WhiteType "human"]
[BlackType "human"]

1. Kg2 g4 {Black MUST play 1...g4, or 2...g4, otherwise the mate is
shorter than 69 moves} (1. .. Ka8 2. Kf1 Kb7? 3. f3! Ka8 4. Kf2 Kb7 5. Ke1
Ka8 6. Kd1 Kb7 7. Kc1 Ka8 8. Kb2 Kb7 9. Ka3 Ka8 10. Kb4 Kb7 11. Ka5 h6 12.
Kb4 Ka8 13. Ka3 Kb7 14. Ka2 Ka8 15. Kb2 Kb7 16. Ka3 h5 17. h3 Ka8 18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24. Ka3 Ka8 25. Kb4 Kb7 26. Ka5 h4 27. Kb4 Ka8 28. Ka3
Kb7 29. Ka2 Ka8 30. Kb2 Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 g4 34. fxg4 g5
35. Kb4 Ka8 36. Ka3 Kb7 37. Kb2 Ka8 38. Kb1 Kb7 39. Kc1 b4 40. cxb4 c3 41.
dxc3 Ka8 42. b5 d2+ 43. Kxd2 cxb5 44. c6 b4 45. c4 b3 46. c7 Kb7 47. a8=Q+
Kxb6 48. c8=Q b2 49. Qcc6#) 2. Kf1 Ka8 3. Ke1 Kb7 4. Kd1 Ka8 5. Kc1 Kb7 6.
Kb2 Ka8 7. Ka3 Kb7 8. Ka2 Ka8 9. Kb2 Kb7 10. Ka3 Ka8 11. Kb4
Kb7 12. Ka5 h6 13. Kb4 Ka8 14. Ka3 Kb7 15. Ka2 Ka8 16. Kb2 Kb7 17. Ka3 Ka8
18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24.
Ka3 Ka8 25. Kb4 Kb7 26. Ka5 g5 27. Kb4 Ka8 28. Ka3 Kb7 29. Ka2 Ka8 30. Kb2
Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 h5 34. Kb4 Ka8 35. Ka3 Kb7 36. Ka2 Ka8
37. Kb2 Kb7 38. Ka3 Ka8 39. Kb4 Kb7 40. Ka5 h4 41. Kb4 Ka8 42. Ka3 Kb7 43.
Ka2 Ka8 44. Kb2 Kb7 45. Ka3 Ka8 46. Kb4 Kb7 47. Ka5 h3 48. Kb4 Ka8 49. Ka3
Kb7 50. Ka2 Ka8 51. Kb2 Kb7 52. Ka3 Ka8 53. Kb4 Kb7 54. Ka5 g3 55. fxg3 g4
56. Kb4 Ka8 57. Ka3 Kb7 58. Ka2 Ka8 59. Kb2 Kb7 60. Ka3 Ka8 61. Kb4 Kb7 62.
Ka5 b4 63. Kxb4 Ka8 64. Ka5 Kb7 65. a8=Q+ Kxa8 66. Ka6 Kb8 67. b7 Kc7 68.
Ka7 Kd8 69. b8=Q# 1-0
[/pgn]

If I am wrong or perhaps you or someone else can refine it further, then please post. I think my pgn gives the gist of how this one works though.
Hi Andrew,
isn't 58...b4 better than your 58...Ka8?

After 58...Ka8 is 59.Kb2 a mate in 11
After 58...b4 best move is 59.cxb4 with mate in 13

so overall a mate in 71
acase
Posts: 983
Joined: Wed Mar 15, 2006 1:14 am
Location: Columbus, Ohio USA
Full name: Andrew R Case

Re: 8 hard positions from the Chest database

Post by acase »

Paloma wrote: Sat Mar 30, 2024 12:42 am
acase wrote: Fri Mar 29, 2024 11:41 pm Hi Dann, here is what I have on this one (mate in 69):

[pgn][Event "Mate in 69"]
[Site "Columbus, Ohio"]
[Date "2024.03.29"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "1-0"]
[Time "17:15:07"]
[TimeControl "0"]
[SetUp "1"]
[FEN "8/Pk2p1pp/1Pp1P3/1pP3p1/2p5/2Pp4/3P1P1P/7K w - - 0 1"]
[Termination "normal"]
[PlyCount "137"]
[WhiteType "human"]
[BlackType "human"]

1. Kg2 g4 {Black MUST play 1...g4, or 2...g4, otherwise the mate is
shorter than 69 moves} (1. .. Ka8 2. Kf1 Kb7? 3. f3! Ka8 4. Kf2 Kb7 5. Ke1
Ka8 6. Kd1 Kb7 7. Kc1 Ka8 8. Kb2 Kb7 9. Ka3 Ka8 10. Kb4 Kb7 11. Ka5 h6 12.
Kb4 Ka8 13. Ka3 Kb7 14. Ka2 Ka8 15. Kb2 Kb7 16. Ka3 h5 17. h3 Ka8 18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24. Ka3 Ka8 25. Kb4 Kb7 26. Ka5 h4 27. Kb4 Ka8 28. Ka3
Kb7 29. Ka2 Ka8 30. Kb2 Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 g4 34. fxg4 g5
35. Kb4 Ka8 36. Ka3 Kb7 37. Kb2 Ka8 38. Kb1 Kb7 39. Kc1 b4 40. cxb4 c3 41.
dxc3 Ka8 42. b5 d2+ 43. Kxd2 cxb5 44. c6 b4 45. c4 b3 46. c7 Kb7 47. a8=Q+
Kxb6 48. c8=Q b2 49. Qcc6#) 2. Kf1 Ka8 3. Ke1 Kb7 4. Kd1 Ka8 5. Kc1 Kb7 6.
Kb2 Ka8 7. Ka3 Kb7 8. Ka2 Ka8 9. Kb2 Kb7 10. Ka3 Ka8 11. Kb4
Kb7 12. Ka5 h6 13. Kb4 Ka8 14. Ka3 Kb7 15. Ka2 Ka8 16. Kb2 Kb7 17. Ka3 Ka8
18. Kb4 Kb7 19. Ka5 g6 20. Kb4 Ka8 21. Ka3 Kb7 22. Ka2 Ka8 23. Kb2 Kb7 24.
Ka3 Ka8 25. Kb4 Kb7 26. Ka5 g5 27. Kb4 Ka8 28. Ka3 Kb7 29. Ka2 Ka8 30. Kb2
Kb7 31. Ka3 Ka8 32. Kb4 Kb7 33. Ka5 h5 34. Kb4 Ka8 35. Ka3 Kb7 36. Ka2 Ka8
37. Kb2 Kb7 38. Ka3 Ka8 39. Kb4 Kb7 40. Ka5 h4 41. Kb4 Ka8 42. Ka3 Kb7 43.
Ka2 Ka8 44. Kb2 Kb7 45. Ka3 Ka8 46. Kb4 Kb7 47. Ka5 h3 48. Kb4 Ka8 49. Ka3
Kb7 50. Ka2 Ka8 51. Kb2 Kb7 52. Ka3 Ka8 53. Kb4 Kb7 54. Ka5 g3 55. fxg3 g4
56. Kb4 Ka8 57. Ka3 Kb7 58. Ka2 Ka8 59. Kb2 Kb7 60. Ka3 Ka8 61. Kb4 Kb7 62.
Ka5 b4 63. Kxb4 Ka8 64. Ka5 Kb7 65. a8=Q+ Kxa8 66. Ka6 Kb8 67. b7 Kc7 68.
Ka7 Kd8 69. b8=Q# 1-0
[/pgn]

If I am wrong or perhaps you or someone else can refine it further, then please post. I think my pgn gives the gist of how this one works though.
Hi Andrew,
isn't 58...b4 better than your 58...Ka8?

After 58...Ka8 is 59.Kb2 a mate in 11
After 58...b4 best move is 59.cxb4 with mate in 13

so overall a mate in 71
Hi Herbert,

You are of course correct about move 58. for Black, but there may be somewhere earlier in my pgn where I messed up that could be corrected to make it a mate in 69, at least we have a blueprint for how it works now.
User avatar
Ajedrecista
Posts: 1971
Joined: Wed Jul 13, 2011 9:04 pm
Location: Madrid, Spain.

Re: 8 hard positions from the Chest database.

Post by Ajedrecista »

Hello:

Some problems lack of the original source. The stipulated #69 problem (K+8P vs K+8P) is from 1996 by Miodrag Radomirović (4th Honourable Mention of Mat Plus Informal Tourney: Moremovers 1996), which is based in other problem of 1962 by Knöppel:

https://yacpdb.org/#103087 (1996).
https://yacpdb.org/#103086 (1962).

The original source of the stipulated #69 problem is reachable from here, downloading the ZIP file of the 'Other Archives' section, then going to ty96dn.htm file of the download, after unzip. It says the following:
Mat Plus wrote:Good extension of existing task. 1.Kg2! [White has to avoid check and stop b-c-d- chain: 1.h3? (1.Kg1?) b4! 2.cb4 c3 3.b5 c2! 4.bc6 Ka8 5.c7 c1Q+! 6.Kg2 Qc5!] 1... Ka8 [Black has not tempo-check on first rank any more (1... b4??), but White still has to hurry because now he has not tempo-check 2.bc6 (2.h3?? b4!)] 2.Kf1 g4! [High time for Black to secure more space (time) on the right-hand side of the board (2... Kb7? 3.h3/f3!)] 3.Ke1 Kb7 4.Kd1 5.Kc1 6.Kb1!! (6.Kb2? Ka8 7.Ka3? Kb7 ... 9.Ka5 Kb7!; 7.Ka2? b4! 8.Kb2 b3! - WK is too far from d1) 6... Ka8 7.Kb2! Kb7 8.Ka3 Ka8 9.Kb4 Kb7 10.Ka5 h6 11.Kb4 etc., as from 8th move in Knöppel's problem (diagram below).

{Below is represented Knöppel's problem of 1962 with the following solution:

1.Kb4 Ka8 2.Ka3 Kb7 3.Ka2 4.Kb2 5.Ka3 6.Kb4 7.Ka5 h6 8.Kb4 9-14.Ka5 h5 15-21.Ka5 h4 28.Ka5 h3 35.Ka5 g6 42.Ka5 g5 49.Ka5 g3 50.fg3 g4 51.Kb4 55.Kc1 59.Ka5 b4 60.Kb4: 61.Ka5 Kb7 62.a8Q+ Ka8: 63.Ka6 Kb8 64.b7 Kc7 65.Ka7 Kd8 66.b8Q#}.
The original source seemingly disagrees with Andrew's solution in white's 6th move (6.Kb2? Ka8 7.Ka3? Kb7 ... 9.Ka5 Kb7! [...]), but the original solution shows a too early attempt to reach a5, which Andrew's line does not.

Just for comparison, the full solution of Knöppel's problem can be found here:

[pgn][Event ""]
[Site ""]
[Date "1962"]
[Round ""]
[White "Jan Knoppel"]
[Black ""]
[Result "1-0"]
[SetUp "1"]
[FEN "8/Pk2p1pp/1Pp1P3/KpP5/2p3p1/2Pp4/3P1P1P/8 w - - 0 1"]
[PlyCount "125"]
[EventDate "1962"]

1. Kb4 Ka8 2. Ka3 Kb7 3. Ka2 (3. Kb2 $2 Ka8 4. Kc1 (4. Ka2 b4) 4... Kb7 5. Kb1 Ka8 6. Kb2) 3... Ka8 4. Kb2 Kb7 5. Ka3 Ka8 6. Kb4 Kb7 7. Ka5 h6 8. Kb4 Ka8 9. Ka3 Kb7 10. Ka2 Ka8 11. Kb2 Kb7 12. Ka3 Ka8 13. Kb4 Kb7 14. Ka5 h5 15. Kb4 Ka8 16. Ka3 Kb7 17. Ka2 Ka8 18. Kb2 Kb7 19. Ka3 Ka8 20. Kb4 Kb7 21. Ka5 h4 22. Kb4 Ka8 23. Ka3 Kb7 24. Ka2 Ka8 25. Kb2 Kb7 26. Ka3 Ka8 27. Kb4 Kb7 28. Ka5 g6 29. Kb4 Ka8 30. Ka3 Kb7 31. Ka2 Ka8 32. Kb2 Kb7 33. Ka3 Ka8 34. Kb4 Kb7 35. Ka5 g5 36. Kb4 Ka8 37. Ka3 Kb7 38. Ka2 Ka8 39. Kb2 Kb7 40. Ka3 Ka8 41. Kb4 Kb7 42. Ka5 h3 43. Kb4 Ka8 44. Ka3 Kb7 45. Ka2 Ka8 46. Kb2 Kb7 47. Ka3 Ka8 48. Kb4 Kb7 49. Ka5 g3 50. fxg3 g4 51. Kb4 Ka8 52. Ka3 Kb7 53. Ka2 Ka8 54. Kb2 Kb7 55. Ka3 Ka8 56. Kb4 Kb7 57. Ka5 b4 58. Kxb4 Ka8 59. Ka5 Kb7 60. a8=Q+ Kxa8 61. Ka6 Kb8 62. b7 Kc7 63. Ka7 1-0[/pgn]

If I am not wrong, the critical point after 53.Ka2 in Knöppel's problem is replicated in Andrew's line, with Knöppel suggesting 53... Ka8 again, as Andrew (58... Ka8), instead of ... b4 by Herbert, whose claim can be easily checked with Chest:

Code: Select all

FEN: 8/Pk2p3/1Pp1P3/1pP5/2p3p1/2Pp2Pp/K2P3P/8 b - - 5 53

ChestUCI:
FEN: 8/Pk2p3/1Pp1P3/1pP5/2p3p1/2Pp2Pp/K2P3P/8 b - -   (9+8)
Stellungs-Analyse:  S:2/4
Suche nach Matt in -14 ...  (Hash=64MB)
Suche abgeschlossen ...  (Zeit=8.75s)
Matt in -13 gefunden !  (4 Lösungen in 00:08)
  1/13	00:09	   6.653.967	760.540	-M1	Kb7a6 a7a8Q+
  1/13	00:09	   6.653.967	760.540	-M1	Kb7c8 a7a8Q+
 11/13	00:09	   6.653.967	760.540	-M11	Kb7a8 Ka2b2 Ka8b7 Kb2a3 Kb7a8 Ka3b4 Ka8b7 Kb4a5 b5b4 Ka5xb4 Kb7a8 Kb4a5 Ka8b7 a7a8Q+ Kb7xa8 Ka5a6 Ka8b8 b6b7 Kb8c7 Ka6a7 Kc7d8 b7b8Q+
 13/13	00:09	   6.653.967	760.540	-M13	b5b4 c3xb4 c4c3 b4b5 c3xd2 b5xc6+ Kb7xc6 a7a8Q+ Kc6xc5 Qa8a5+ Kc5c6 Qa5xd2 Kc6xb6 Qd2xd3 Kb6c6 Qd3d7+ Kc6b6 Ka2b2 Kb6a6 Kb2c3 Ka6b6 Kc3c4 Kb6a6 Kc4c5 Ka6a5 Qd7b5+
Regards from Spain.

Ajedrecista.