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Subject: Re: Troitzky 1914, ultimate test

Author: Jim Monaghan

Date: 09:33:29 06/15/01

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On June 15, 2001 at 10:06:00, Uri Blass wrote:

>On June 15, 2001 at 09:25:16, Jim Monaghan wrote:
>
>>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.
>
>1.Be1 Rh6 2.Kg7 Rh5 3.Kxf7 seems to be a shorter win for white in this line.
>What did I miss?
>
>Uri

Uri,

It makes sense to eliminate the pawn to shorten the solution. But:

1. Be1 Rh6 2. Kg7 Rh5 3. Kxf7 Rh6 4. Kf8 Rh5 5. Kg7 d5 6. Kf8 Rh6 7. Kf7
Nd6+ (7. Kg8 Nf6+). How does White triangulate to have his King at g7 when Black
wants to play Rh5-h6? I think this draws only.

Jim






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