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Subject: Re: Hard pawn endgame?

Author: Uri Blass

Date: 07:13:27 11/17/05

Go up one level in this thread


On November 17, 2005 at 09:58:11, Uri Blass wrote:

>On November 17, 2005 at 09:41:12, Uri Blass wrote:
>
>>On November 17, 2005 at 08:59:39, Bernhard Bauer wrote:
>>
>>>This pawn endgame has only 7 pieces.
>>>Yace shines bright in this type of position.
>>>Gambitfruit finds the right move early, but fails to give a high score.
>>>Running it for 15 min on a AMD XP 1800 MHz let it reach a depth of 31,
>>>but the score remains at 1.76.
>>>What's the reason?
>>>Kind regards
>>>Bernhard
>>
>>I do not know but I guess that some random move generator can get the correct
>>score even faster than yace if it is lucky
>>
>>Maybe yace is lucky
>>Note that even some plies after the root position after white lost a tempo
>>commercial Fruit does not see nothing at depth 36(white move by yace when black
>>moves by fruit)
>>
>>1.Ke4 Ke8 2.Ke3 Ke7 3.Kf3 Kd6 4.Ke4 Ke7 5.Ke5
>>
>>New game,
>>[D]8/4k1p1/8/4KPp1/6P1/7P/8/8 b - - 0 1
>>
>>Analysis by Fruit 2.2.1:
>>
>>5...Kd7
>>  +-  (2.14)   Depth: 1/1   00:00:00
>>5...Kd7 6.Kd4
>>  +-  (1.94)   Depth: 2/3   00:00:00
>>5...Kd7 6.Kd5 Ke7
>>  +-  (2.14)   Depth: 3/4   00:00:00
>>5...Kd7 6.f6 Ke8 7.fxg7 Kf7
>>  +-  (3.61)   Depth: 4/6   00:00:00
>>5...Kf7 6.Kd4 Ke7 7.Kd5
>>  +-  (1.94)   Depth: 4/7   00:00:00
>>5...Kf7 6.Kd4 g6 7.Ke5 gxf5 8.gxf5
>>  +-  (1.75)   Depth: 5/7   00:00:00
>>5...Kf7 6.Kd4 Kf6 7.Kd5 g6 8.fxg6 Kxg6
>>  +-  (1.46)   Depth: 6/8   00:00:00  1kN
>>5...Kf7 6.Kd4 Kf6 7.Kd5 Ke7 8.Kc5 Kf6
>>  +-  (2.02)   Depth: 7/9   00:00:00  2kN, tb=3
>>5...Kf7 6.Kd6 Kf6 7.Kd5 g6 8.Ke4 Kf7 9.Ke5 gxf5 10.gxf5
>>  +-  (1.75)   Depth: 8/11   00:00:00  6kN, tb=5
>>5...Kf7 6.Kd6 Kf6 7.Kd5 g6 8.Ke4 Kf7 9.Ke5 gxf5 10.gxf5
>>  +-  (1.75)   Depth: 9/11   00:00:00  8kN, tb=6
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Kd6 9.Kc4 Ke5 10.Kc5
>>  +-  (1.58)   Depth: 10/13   00:00:00  13kN, tb=6
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Kf7 9.Kc4 g6 10.Kd4 gxf5 11.gxf5
>>  +-  (1.55)   Depth: 11/15   00:00:00  21kN, tb=8
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kd4 Kf7 10.Kc4 g6 11.Kd4 gxf5 12.gxf5
>>  +-  (1.55)   Depth: 12/15   00:00:00  31kN, tb=10
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kd4 Kf7 10.Kc4 g6 11.Kd4 gxf5 12.gxf5
>>  +-  (1.55)   Depth: 13/17   00:00:01  48kN, tb=13
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Ke8 9.Kc5 Ke7 10.Kc4 Kf7 11.Kc3 g6 12.Kd4 gxf5
>>13.gxf5
>>  +-  (1.55)   Depth: 14/19   00:00:01  73kN, tb=13
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Ke8 9.Kc5 Ke7 10.Kc4 Kf7 11.Kd3 g6 12.Kd4 gxf5
>>13.gxf5
>>  +-  (1.55)   Depth: 15/19   00:00:01  96kN, tb=22
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Ke8 9.Kc5 Ke7 10.Kc4 Kf6 11.Kd3 Kf7 12.Kc3 g6
>>13.Kd4 gxf5 14.gxf5
>>  +-  (1.55)   Depth: 16/22   00:00:01  129kN, tb=37
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kd3 g6
>>13.Kd4 gxf5 14.gxf5
>>  +-  (1.55)   Depth: 17/26   00:00:01  207kN, tb=74
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Kf7 11.Kc6 Ke7 12.Kd5 Kf7
>>13.Kc5 g6 14.Kd5 gxf5 15.gxf5
>>  +-  (1.55)   Depth: 18/28   00:00:01  317kN, tb=140
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Ke7 12.Kd3 Kf7
>>13.Kc3 g6 14.Kd4 gxf5 15.gxf5
>>  +-  (1.55)   Depth: 19/32   00:00:01  415kN, tb=345
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kd3 Ke8
>>13.Kc2 Kf7 14.Kc3 g6 15.Kd4 gxf5 16.gxf5
>>  +-  (1.55)   Depth: 20/33   00:00:01  499kN, tb=546
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kd3 Ke8
>>13.Kc2 Kf7 14.Kc3 g6 15.Kd4 gxf5 16.gxf5
>>  +-  (1.55)   Depth: 21/35   00:00:01  611kN, tb=732
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Kf7 11.Kb6 Ke7 12.Ka5 Kf7
>>13.Kb5 Ke8 14.Kc4 Kf7 15.Kc5 g6 16.Kd5 gxf5 17.gxf5
>>  +-  (1.55)   Depth: 22/39   00:00:01  911kN, tb=1080
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc5 Ke7 14.Kd5 Kf7 15.Kc6 g6 16.Kd5 gxf5 17.gxf5
>>  +-  (1.55)   Depth: 23/39   00:00:02  1089kN, tb=1911
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kd3 Ke8
>>13.Ke2 Ke7 14.Kd2 Kf6 15.Kd3 Kf7 16.Kc3 g6 17.Kd4 gxf5 18.gxf5
>>  +-  (1.55)   Depth: 24/40   00:00:02  1402kN, tb=1957
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kd3 Ke8
>>13.Kc3 Ke7 14.Kd4 Kf6 15.Kc5 Kf7 16.Kc6 g6 17.Kd5 gxf5 18.gxf5
>>  +-  (1.55)   Depth: 25/43   00:00:02  1935kN, tb=2443
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kc7 Ke7 15.Kb6 Kf6 16.Kc5 Kf7 17.Kc6 g6 18.Kd5 gxf5 19.gxf5
>>  +-  (1.55)   Depth: 26/43   00:00:02  2708kN, tb=2971
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kd7 Kf8 15.Ke6 Ke8 16.Kd6 Kf7 17.Kc6 g6 18.Kd5 gxf5 19.gxf5
>>  +-  (1.55)   Depth: 27/48   00:00:05  6894kN, tb=4130
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc5 Ke7 14.Kd4 Kf6 15.Kd3 Ke7 16.Ke2 Kf6 17.Kd2 Kf7 18.Kc3 g6 19.Kd4 gxf5
>>20.gxf5
>>  +-  (1.55)   Depth: 28/48   00:00:07  9576kN, tb=4949
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kd7 Kf8 15.Kc7 Kf7 16.Kb7 Ke7 17.Kb6 Kf7 18.Kc6 g6 19.Kd5 gxf5
>>20.gxf5
>>  +-  (1.55)   Depth: 29/50   00:00:08  11757kN, tb=5637
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kd7 Kf8 15.Kd6 Kf7 16.Kc7 Ke7 17.Kc8 Kf6 18.Kd7 Kf7 19.Kc6 g6
>>20.Kd5 gxf5 21.gxf5
>>  +-  (1.55)   Depth: 30/53   00:00:10  14283kN, tb=6738
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kc3 Ke8
>>13.Kc2 Kf7 14.Kd2 Ke7 15.Ke2 Kf6 16.Kd3 Ke7 17.Kd4 Kf6 18.Kc5 Kf7 19.Kc6 g6
>>20.Kd5 gxf5 21.gxf5
>>  +-  (1.55)   Depth: 31/54   00:00:14  20337kN, tb=7717
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kc3 Ke8
>>13.Kc2 Kf7 14.Kd3 Ke8 15.Ke2 Ke7 16.Kf1 Kf6 17.Kf2 Kf7 18.Kg3 g6 19.Kf3 Ke7
>>20.Ke3 Kf7 21.Kd4
>>  +-  (1.55)   Depth: 32/55   00:00:21  29121kN, tb=10243
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kd7 Kf8 15.Kd6 Kf7 16.Kc7 Ke7 17.Kb7 Kf6 18.Kc8 Ke7 19.Kc7 Kf7
>>20.Kc6 g6 21.Kd5
>>  +-  (1.55)   Depth: 33/55   00:00:27  37834kN, tb=11880
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kb5 Ke8
>>13.Kc6 Kf7 14.Kd7 Kf8 15.Kd6 Kf7 16.Kc6 Ke7 17.Kc7 Kf6 18.Kd7 Kf7 19.Kd8 Kf8
>>20.Kc8 g6 21.Kc7
>>  +-  (1.55)   Depth: 34/57   00:00:37  52206kN, tb=13706
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kc3 Ke8
>>13.Kc2 Kf7 14.Kd3 Ke8 15.Kd2 Ke7 16.Ke3 Kf6 17.Kd3 Ke7 18.Kd4 Kf6 19.Kc3 Ke7
>>20.Kd2 g6 21.Kd3
>>  +-  (1.55)   Depth: 35/58   00:00:48  70993kN, tb=15780
>>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kc5 Ke8 11.Kc4 Kf7 12.Kc3 Ke8
>>13.Kc2 Kf7 14.Kd3 Ke8 15.Kd2 Ke7 16.Ke1 Kf7 17.Ke2 Ke7 18.Kf1 Kf6 19.Kf2 Kf7
>>20.Kg3 g6 21.Kf3
>>  +-  (1.55)   Depth: 36/67   00:01:13  109991kN, tb=20984
>>
>>(,  17.11.2005)
>
>Note that history pruning is one of the reasons that fruit could not see the
>mate
>
>Fruit without history pruning
>
>New game,
>8/4k1p1/8/4KPp1/6P1/7P/8/8 b - - 0 1
>
>Analysis by Fruit 2.2.1:
>
>5...Kd7
>  +-  (2.14)   Depth: 1/1   00:00:00
>5...Kd7 6.Kd4
>  +-  (1.94)   Depth: 2/3   00:00:00
>5...Kd7 6.Kd5 Ke7
>  +-  (2.14)   Depth: 3/4   00:00:00
>5...Kd7 6.f6 Ke8 7.fxg7 Kf7
>  +-  (3.61)   Depth: 4/6   00:00:00
>5...Kf7 6.Kd4 Ke7 7.Kd5
>  +-  (1.94)   Depth: 4/7   00:00:00
>5...Kf7 6.Kd4 g6 7.Ke5 gxf5 8.gxf5
>  +-  (1.75)   Depth: 5/7   00:00:00
>5...Kf7 6.Kd4 Kf6 7.Kd5 g6 8.fxg6 Kxg6
>  +-  (1.46)   Depth: 6/8   00:00:00  1kN
>5...Kf7 6.Kd4 Kf6 7.Kd5 Ke7 8.Kc5 Kf6
>  +-  (2.02)   Depth: 7/9   00:00:00  3kN, tb=3
>5...Kf7 6.Kd6 Kf6 7.Kd5 g6 8.Ke4 Kf7 9.Ke5 gxf5 10.gxf5
>  +-  (1.75)   Depth: 8/11   00:00:00  6kN, tb=5
>5...Kf7 6.Kd6 Kf6 7.Kd5 g6 8.Ke4 Kf7 9.Ke5 gxf5 10.gxf5
>  +-  (1.75)   Depth: 9/12   00:00:01  9kN, tb=6
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Kd6 9.Kc4 Ke5 10.Kc5
>  +-  (1.58)   Depth: 10/13   00:00:01  16kN, tb=6
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kd4 Kf7 9.Kc4 g6 10.Kd4 gxf5 11.gxf5
>  +-  (1.55)   Depth: 11/15   00:00:01  26kN, tb=8
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kd4 Kf7 10.Kc4 g6 11.Kd4 gxf5 12.gxf5
>  +-  (1.55)   Depth: 12/15   00:00:01  40kN, tb=10
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kd4 Kf7 10.Kc4 g6 11.Kd4 gxf5 12.gxf5
>  +-  (1.55)   Depth: 13/16   00:00:01  65kN, tb=13
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Ke7 10.Kd4 Kf7 11.Kd3 g6 12.Kd4 gxf5
>13.gxf5
>  +-  (1.55)   Depth: 14/18   00:00:01  96kN, tb=13
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Ke7 10.Kd4 Kf7 11.Kd3 g6 12.Kd4 gxf5
>13.gxf5
>  +-  (1.55)   Depth: 15/19   00:00:01  136kN, tb=23
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Kf7 10.Kd3 Ke7 11.Kd4 Kf7 12.Kc4 g6
>13.Kd4 gxf5 14.gxf5
>  +-  (1.55)   Depth: 16/21   00:00:01  182kN, tb=37
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Kf7 10.Kd3 Ke7 11.Kd4 Kf7 12.Kc4 g6
>13.Kd5 gxf5 14.gxf5
>  +-  (1.55)   Depth: 17/23   00:00:01  233kN, tb=130
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Kf7 10.Kd3 Ke7 11.Ke3 Kf6 12.Kd2 Kf7
>13.Kc3 g6 14.Kd4 gxf5 15.gxf5
>  +-  (1.55)   Depth: 18/25   00:00:01  313kN, tb=279
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc5 Ke8 9.Kc4 Kf7 10.Kd3 Ke7 11.Ke3 Kf6 12.Kd2 Kf7
>13.Kc3 g6 14.Kd4 gxf5 15.gxf5
>  +-  (1.55)   Depth: 19/29   00:00:01  448kN, tb=549
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc4 Kf6 9.Kd4 Ke7 10.Kd5 Kf7 11.Kc5 Ke7 12.Kb4 Kf6
>13.Kb5 Kf7 14.Kc6 g6 15.Kd5 gxf5 16.gxf5
>  +-  (1.55)   Depth: 20/32   00:00:01  1006kN, tb=810
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Ke8 9.Kd6 Kf8 10.Kc5 Ke7 11.Kd5 Kf7 12.Kd4 Ke7
>13.Kd3 Kf7 14.Kc4 g6 15.Kd5 gxf5 16.gxf5
>  +-  (1.55)   Depth: 21/35   00:00:01  2293kN, tb=1210
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Kf7 12.Kc5 Ke7
>13.Kc4 Kf6 14.Kd4 Kf7 15.Kd3 g6 16.Ke4 gxf5+ 17.gxf5
>  +-  (1.55)   Depth: 22/38   00:00:02  3036kN, tb=1728
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kc7 Kf6
>13.Kb6 Ke7 14.Kc5 Kf7 15.Kc4 g6 16.Kd4 gxf5 17.gxf5
>  +-  (1.55)   Depth: 23/43   00:00:02  3462kN, tb=2188
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kd5 Kd7
>13.Kc5 Ke7 14.Kd4 Ke8 15.Kc4 Kf7 16.Kd3 g6 17.Ke4 gxf5+ 18.gxf5
>  +-  (1.55)   Depth: 24/43   00:00:03  4120kN, tb=3435
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kd5 Kd7
>13.Kc5 Ke7 14.Kd4 Kf6 15.Kd3 Kf7 16.Kc3 g6 17.Kd4 gxf5 18.gxf5
>  +-  (1.55)   Depth: 25/54   00:00:04  5313kN, tb=4586
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kd5 Kd7
>13.Kc5 Kc7 14.Kd4 Kd6 15.Kc3 Ke7 16.Kc4 Kf7 17.Kc5 g6 18.Kd5 gxf5 19.gxf5
>  +-  (1.55)   Depth: 26/57   00:00:06  7898kN, tb=4847
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kd5 Kd7
>13.Kc5 Kc7 14.Kd4 Kd6 15.Kd3 Ke7 16.Kc2 Kf7 17.Kc3 g6 18.Kd4 gxf5 19.gxf5
>  +-  (1.55)   Depth: 27/58   00:00:10  14835kN, tb=6463
>5...Kf7 6.Kd6 Kf6 7.Kd5 Ke7 8.Kc6 Kf6 9.Kd6 Kf7 10.Kd7 Kf8 11.Kc6 Ke7 12.Kc5 Kf7
>13.Kc4 Kf6 14.Kd4 Ke7 15.Kd3 Kf6 16.Kc4 Ke7 17.Kd5 Kf7 18.Kc5 g6 19.Kd5 gxf5
>20.gxf5
>  +-  (1.55)   Depth: 28/58   00:00:13  19646kN, tb=7497
>5...Kf7 6.Kd5 Ke7 7.Kc6 Kf6 8.Kd6 Kf7 9.Kd7 Kf8 10.Ke6 Ke8 11.f6 g6 12.f7+ Kf8
>13.Kd6 Kxf7 14.Kd7 Kf6 15.Ke8 Kg7 16.Ke7 Kh7 17.Kf7 Kh6 18.Kf6 Kh7 19.Kxg5
>  +-  (#30)   Depth: 29/60   00:03:18  269992kN, tb=19486
>
>(,  17.11.2005)
>
>Note that fruit probably cannot see it even with no pruning from the root
>position in a reasonable time because as you can see the capture that leads to
>KPP vs KP tablebases endgame happen only after 37 plies from the root position
>so asking it to find it at depth that is smaller than depth 37 is probably
>impossible.
>
>I also guess that some other pruning may be a problem for fruit to find it
>because sacrificing f7 is a clear candidate to prune as illogical move.
>
>Uri

The original position is mate in 36 based on backward analysis by yace

I see that the line is even one move longer then the line that I originally gave
so it seems that the capture 20.Kxg5 happens only at ply 39 from the root so it
is not surprising that programs have big problem here.

New game,
8/4k1p1/8/4KPp1/6P1/7P/8/8 w - - 0 1

Analysis by Yace 0.99.87:

1.f6+ gxf6+ 2.Kf5
  =  (0.23)   Depth: 1   00:00:00
1.Kd5
  +-  (2.32)   Depth: 1   00:00:00
1.Ke4 Ke8 2.Ke3 Kd7 3.Kd3 Ke8 4.Ke4 Kd8 5.Kd4 Ke7 6.Ke5 Kf7 7.Kd5 Ke7 8.Kc6 Kf8
9.Kd6 Kf7 10.Kd7 Kf8 11.Ke6 Ke8 12.f6 g6 13.f7+ Kf8 14.Kd6 Kxf7 15.Kd7 Kf8
16.Ke6 Kg7
  +-  (#36)   Depth: 1   00:00:00
1.Ke4 Ke8 2.Ke3 Kd7 3.Kd3 Ke8 4.Ke4 Kd8 5.Kd4 Ke7 6.Ke5 Kf7 7.Kd5 Ke7 8.Kc6 Kf8
9.Kd6 Kf7 10.Kd7 Kf8 11.Ke6 Ke8 12.f6 g6 13.f7+ Kf8 14.Kd6 Kxf7 15.Kd7 Kf8
16.Ke6 Kg7




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