Author: Jim Monaghan
Date: 06:25:16 06/15/01
Go up one level in this thread
On June 15, 2001 at 06:00:35, Andreas Stabel wrote: >On June 15, 2001 at 04:49:59, Uri Blass wrote: > >>On June 15, 2001 at 02:54:51, Dann Corbit wrote: >> >>>On June 15, 2001 at 02:40:05, Jim Monaghan wrote: >>> >>>>Well here it is folks. It's definitely not worth trying. I'm only posting it as >>>>a curiousity. >>>> >>>>White to move and mate in 92 moves. Er, that's 183 plies ... :) >>>> >>>>[D] 7K/5p1p/3p2p1/B5pr/4n1pb/3N1bk1/4prn1/6RR w - - 0 1 >>> >>>Don't just leave us hanging! >>> >>>Be1 looks forced for sure. Then what? ... f5? ... d5? >>>Where can I find the move sequence that leads to inescapable victory? >> >>I did not investigate the exact number of moves to mate but >>I can explain the idea white needs to waste tempos in order to force black to >>play pawn moves and finally to lose the rook and the game. >> >>The idea of a simple traingle does not work because the black knight can play a >>check move with the knight, free the pieces, and win the game so we need to look >>for safe squares for the king. >> >>We can find that all the black squares are safe for the king. >>The white squares are not safe for the king except c2 so we need this square in >>order to lose a tempo. >> >>White can find the following idea of wasting a tempo after Be1 by 22 plies >> >>Kh8-g7-f8-e7-d8-c7-b6-a5-b4-a3-b2-c2-c1-b2-a3-b4-a5-b6-c7-d8-e7-f8-g7 >> >>Black can play all the time Rh6-Rh5 moves but when the king gets into g7 black >>need to move a pawn in order not to lose the rook >>playing f7-f6 gives white the g8 square so it does not significantly help black. >>Black also needs to play d6-d5 in order to prevent Kf7 and after these moves >>black has 4 pawns moves(f5,f4,d4,h6) so white needs a lot of moves to convince >>black to play these moves and avoid the Rh6-Rh5 story. >> >>Uri > >Before d6-d5 the f7 square is safe for the king or alternatively before f6-f5 >the g8 square is safe for the king, so the first time the king doesn't have to >go all the way to c2. After h7-h6, the rook has no moves, so the mate follows >immediately. From this I get the solution below which is "only" 70 moves. >What did I miss ? > >1. Be1 f6 2. Kg7 d5 3. Kg8 Rh6 4. Kf8 Rh5 5. Kg7 d4 6. Kf8 Rh6 7. Ke7 Rh5 >8. Kd8 Rh6 9. Kc7 Rh5 10. Kb6 Rh6 11. Ka5 Rh5 12. Kb4 Rh6 13. Ka3 Rh5 14. >Kb2 Rh6 15. Kc2 Rh5 16. Kc1 Rh6 17. Kb2 Rh5 18. Ka3 Rh6 19. Kb4 Rh5 20. Ka5 >Rh6 21. Kb6 Rh5 22. Kc7 Rh6 23. Kd8 Rh5 24. Ke7 Rh6 25. Kf8 Rh5 26. Kg7 f5 >27. Kf8 Rh6 28. Ke7 Rh5 29. Kd8 Rh6 30. Kc7 Rh5 31. Kb6 Rh6 32. Ka5 Rh5 33. >Kb4 Rh6 34. Ka3 Rh5 35. Kb2 Rh6 36. Kc2 Rh5 37. Kc1 Rh6 38. Kb2 Rh5 39. Ka3 >Rh6 40. Kb4 Rh5 41. Ka5 Rh6 42. Kb6 Rh5 43. Kc7 Rh6 44. Kd8 Rh5 45. Ke7 Rh6 >46. Kf8 Rh5 47. Kg7 f4 48. Kf8 Rh6 49. Ke7 Rh5 50. Kd8 Rh6 51. Kc7 Rh5 52. >Kb6 Rh6 53. Ka5 Rh5 54. Kb4 Rh6 55. Ka3 Rh5 56. Kb2 Rh6 57. Kc2 Rh5 58. Kc1 >Rh6 59. Kb2 Rh5 60. Ka3 Rh6 61. Kb4 Rh5 62. Ka5 Rh6 63. Kb6 Rh5 64. Kc7 Rh6 >65. Kd8 Rh5 66. Ke7 Rh6 67. Kf8 Rh5 68. Kg7 h6 69. Kf8 Nf6 70. Bxf2# 1-0 > >Regards >Andreas Stabel Very good guys ... that's the right track. I will end the suspense. The position is from "360 Brilliant and Instructive Endgames", an addendum to #127. Troitzky's note follows: "Here after 1.Be1 Rh6 2.Kg7 Rh5; White's king returns six times to g7 waiting for Black's move Rh6. But Black instead moves his pawns forcing prolonged marches of White's King: first time to c8, second time after 11. Kg7 d5 to a8; third time after 24. Kg7 d4 to c2; fourth time after 48. Kg7 to g8; fifth time after 48. Kg7 f5 to c2; sixth time after 69. Kg7 f4 to c2. Finally 90. Kg7 forces Black to move 90 ... Rh6 or h7-h6 and mate follows in two moves." Congratulations Uri and Andreas ... fine piece of analysis. Regards, Jim
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