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Subject: Re: Anyone analyzed Nunn Endgame Testposition 08? S8 after 31h

Author: Joachim Rang

Date: 16:40:30 06/21/04

Go up one level in this thread


On June 20, 2004 at 17:17:16, Vincent Lejeune wrote:

>Shredder 8; amd 2800+; 384 MB hash
>
>Before 1.c6
>
>1.Fh8 Rd3 2.Ff6 Rc2 3.Fd8 f3 4.Re3 Rc3 5.Fc7 Rb3 6.c6 Rxa3 7.Rd4 Fxc6 8.Rc5 f2
>9.Fe5 f1D 10.Fb2+ Rxb2 11.Rb6 a5 12.bxa5 Dg2 13.a6 Dxg5
>  -+  (-1.67)   Profondeur: 30/61   00:41:33  1239635kN, tb=207082
>1.Fh8 Rd3 2.Ff6 Rc2 3.Fd8 f3 4.Re3 Rc3 5.Fc7 Rb3 6.Fb6 Fb7 7.Rd2
>  -+  (-1.67)   Profondeur: 31/63   01:12:38  1998865kN, tb=562718
>1.Fd8 f3 2.Fc7 Rd3 3.Fd8 Re4 4.Fc7 Rd3 5.Fd8 Re4 6.Fc7
>  -+  (-1.66)   Profondeur: 31/66   01:50:50  2956003kN, tb=971377
>1.Fd8 f3 2.Fc7 Rd3 3.Fd8 Re4 4.Fc7 Rd3 5.Fd8 Re4 6.Fc7
>  µ  (-1.31)   Profondeur: 31/66   02:25:07  4258268kN, tb=1071534
>1.Fd8 f3 2.Fc7 Rd3 3.Fd8 Re4 4.Fc7 Rd3 5.Fd8 Re4 6.Fc7
>  µ  (-1.31)   Profondeur: 31/66   02:52:19  5724934kN, tb=1081999
>1.Fd8 f3 2.Fc7 Rd3 3.Fd8 Fb7 4.Fb6 Fc6 5.Fc7 Rc4 6.Re3 f2 7.Rxf2 Rd5 8.Re1 Fb7
>  µ  (-1.31)   Profondeur: 32/60   03:27:19  6968786kN, tb=1189981
>1.Fd8 f3 2.Fc7 Fc6 3.Fd8 Rd4 4.Fc7 Rc3 5.Fa5 Fd5 6.c6 Fxc6 7.a4 Fe8 8.Rxf3 bxa4
>9.b5+ Rb3 10.bxa6 a3 11.Fd8 Fb5 12.a7 a2 13.a8D a1D 14.Dxa1
>  µ  (-1.32)   Profondeur: 33/64   05:20:32  10005927kN, tb=2055899
>1.Fd8 f3 2.Fc7 Fc6 3.Fd8 Rd4 4.Fc7 Rc4 5.Re3 f2 6.Rxf2 Rd5 7.Re1 Fb7
>  µ  (-1.32)   Profondeur: 34/65   08:12:45  13746137kN, tb=3993628
>1.Fd8 f3 2.Fc7 Fc6 3.Fd8 Rd4 4.Fc7 Rd3 5.Fa5 Rd4 6.Fc7 Rd3 7.Fa5 Rd4 8.Fc7 Rd3
>  µ  (-1.32)   Profondeur: 35/68   12:17:43  18917445kN, tb=7035988
>1.Fd8 f3 2.Fc7 Fc6 3.Fd8 Rd4 4.Fc7 Rd3 5.Fa5 Rd4 6.Fc7 Rd3 7.Fa5 Rd4 8.Fc7 Rd3
>  µ  (-1.32)   Profondeur: 36/70   19:31:30  27907138kN, tb=12689512
>
>No new line after 31h.
>
>and after 1.c6, with filled hash table :
>
>8/8/p1P2Bp1/1p1b2P1/1P2kp2/P7/5K2/8 b - - 0 1
>
>1...Fxc6 2.Rf1 Rd3 3.Fe5 f3 4.Fg3 Rc2 5.Fe1 Rb3 6.Rf2 Rxa3 7.Rg3 Rb3 8.Rf2 Fd5
>9.Rg3 Rc2 10.Fd2
>  -+  (-2.01)   Profondeur: 26/40   00:03:08  3553kN, tb=490
>1...Fxc6 2.Fd8 Rd3 3.Fb6 Rc3 4.Re2 f3+ 5.Rd1 Rb3 6.Fd8
>  -+  (-2.05)   Profondeur: 27/42   00:03:35  12018kN, tb=2059
>1...Fxc6 2.Fd8 f3 3.Fe7 Rd3 4.Fc5 Rc4 5.Fe3 a5 6.bxa5 Fb7
>  -+  (-2.20)   Profondeur: 28/54   00:04:28  35060kN, tb=8256
>1...Fxc6 2.Fd8 f3 3.Fe7 Rd3 4.Re1 Rc3 5.Fc5 Rb2 6.Rd2 Rxa3 7.Rc3 Ra4 8.Fb6 Fd7
>9.Fc5 a5 10.bxa5 Rxa5 11.Rb3 Fe6+ 12.Rc2 b4 13.Fd4 Ra4 14.Fg1 b3+ 15.Rc1 Rb5
>  -+  (-2.33)   Profondeur: 29/49   00:06:49  94849kN, tb=17901
>1...Fxc6 2.Fd8 f3 3.Fe7 Rd3 4.Re1 Rc3 5.Fc5 Rb2 6.Rd2 Rxa3 7.Rc3 Ra4 8.Fb6 Fd7
>9.Fd4 a5 10.bxa5 Rxa5 11.Rd2 Fc6 12.Fe5 Rb4 13.Re3
>  -+  (-2.41)   Profondeur: 30/53   00:10:35  176310kN, tb=38761
>1...Fxc6 2.Re1 Rd3 3.Fd8 f3 4.Fc7 Rc3 5.Fd6 Rb3 6.Rd1 Rxa3 7.Fc5 Ra4 8.Ff2
>  -+  (-2.45)   Profondeur: 31/54   00:25:47  481237kN, tb=158601
>
>
>On June 18, 2004 at 07:17:04, Joachim Rang wrote:
>
>>Hi,
>>
>>Dr John nunn created a Testset containing 10 endgame positions on the boarder
>>between draw ans won for one side:
>>
>>http://www.geocities.com/CapeCanaveral/Launchpad/2640/pgn/tests/NET.zip
>>
>>The position Nr. 8 is this:
>>
>>[D]8/8/p4Bp1/1pPb2P1/1P2kp2/P7/5K2/8 w - - 0 1
>>
>>Included is the following text:
>>
>>A fantastic position. An opposite-coloured bishop position with equal pawns
>>looks as if it should be a draw, and indeed the players agreed to a draw at
>>this point. However, White a serious problems because of his weak a3-pawn,
>>which cannot be permanently defended by his bishop. Once this pawn has been
>>captured, Black has the chance to make a second passed pawn by playing ...a5,
>>which will stretch White's defence to the utmost. Dvoretsky and Yusupov
>>subjected this ending to detailed analysis, and came to the astonishing
>>conclusion that it is a draw, but only if White starts with the incredible 1
>>c6!!. It is hard to imagine that any machine would find such a move, but who
>>knows what might happen in the future...
>>
>>Anyone analyzed this yet?
>>
>>some lines I can provide:
>>
>>Winning:
>>
>>1.Bf6-g7 Ke4-d3 2.Bg7-e5 f4-f3 3.Be5-g3 Bd5-c6 4.Kf2-f1 Kd3-c3 5.Bg3-e1+ Kc3-b2
>>6.Kf1-f2 Kb2xa3 7.Be1-d2 a6-a5 8.b4xa5 b5-b4 9.Kf2-e3 b4-b3 10.Bd2-c3 b3-b2
>>11.Bc3xb2+ Ka3xb2 12.Ke3-d2 Kb2-b3 13.Kd2-d3 Kb3-b4 14.a5-a6 Kb4xc5 15.a6-a7
>>Bc6-a8 16.Kd3-e3 Kc5-c4
>>
>>Drawing (?):
>>
>>1.c6 Bxc6 2.Ke2 f3+ 3.Kd2 Kf4 4.Bd4 Kxg5 5.Ke3 Kf5 6.Bc5 g5 7.Bd6 g4 8.Bg3 Bd5
>>9.Kd4 Bb7 10.Ke3 Kf6 11.Kf4 Bc8 12.Bh4+ Kf7 13.Bf2 Ke7 14.Ke5 Kd8 15.Kd6 Bf5
>>16.Ke5 Bd7 17.Kd6
>>
>>Thank you in advance for any analysis.
>>
>>regards Joachim


thanks vincent for testing this with Shredder. This is equal or even harder than
the Nolot-Positions and I bet no computer will solve this within 24 hours in the
next 10 years. Anyone who wants to bet?

regards Joachim



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