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Subject: Re: difficult problem

Author: Jim Monaghan

Date: 06:58:27 09/08/02

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Hi Uri and Allan,

I think the position is a draw. Allan's idea I think is that White waltzes his
king up to c8 and then mates with Bb7. Black sacrificing all his pawns will
delay that somewhat.

But if the WK attempts to cross the "Rubicon" (diagonal a8-h1) Black plays
...h2-h1Q+ pretty fast. The only other idea is for the WB to go back along the
diagonal, say Bg2, so as to allow the WK to play Ke4. BUT, this lifts the
stalemate and Black escapes with ...Kb7. If then Kd5 or Kf5+, the position will
still be a draw, as White will have no way of attacking c7 sufficiently to break
through and win all the Black pawns. Black doesn't have control of the white
squares to get his pawn mass going. So this winning attempt will fail with the
result that it's a draw. The two bishops and the WK will waltz around forever up
to 50 moves and then a draw.

This is most probably too hard of a concept for programs. The right evaluation
here is +0.00.

Cheers,
Jim


On September 08, 2002 at 05:30:06, Uri Blass wrote:

>On September 08, 2002 at 04:16:08, Uri Blass wrote:
>
>>On September 08, 2002 at 03:54:40, allan johnson wrote:
>>
>>> How many programmes see that white is winning here?The black king is stalemated
>>>and white's pieces are all on white squares so the white king can simply walk to
>>>c8. Shredder6 and Chess Tiger 14 on my Celeron1.2 show a -6+ for white I guess
>>>that it is too many plies for them.
>>> [D]B7/p1p5/kb1p4/p3p3/P1N2p2/6p1/7p/K7/
>>> Al
>>
>>Yace can see 2.03 pawns improvement for white
>>
>>The score at depth 1 is 7.54 pawns for black
>>The score at depth 19 is 5.51 pawns for black
>>
>>New position
>>[D]B7/p1p5/kb1p4/p3p3/P1N2p2/6p1/7p/K7 w - - 0 1
>>
>>Analysis by Yace 0.99.56:

>>1.Kb2 Bd4+ 2.Kc2 Bc5 3.Bh1 Bb4 4.Kd3 Be1
>>  -+  (-5.51)   Depth: 19   00:13:08  424894kN
>>
>>(blass, tel-aviv 08.09.2002)
>>
>>Uri
>
>progress continues
>
>  -+  (-5.11)   Depth: 20   00:25:48  804415kN
>1.Kb2 Bd4+ 2.Kc2 h1Q 3.Bxh1 g2 4.Bxg2 f3 5.Bxf3 d5
>  -+  (-5.11)   Depth: 20   00:30:24  944391kN
>1.Kb2 Bd4+ 2.Kc2 Bc5 3.Kd3 Bf2 4.Bg2 Bd4 5.Bh1 Bg1 6.Ke4 Be3 7.Nxe3 fxe3 8.Kf3
>e2 9.Kxe2 c5
>  -+  (-4.88)   Depth: 21   01:14:56  2345830kN
>
>(blass, tel-aviv 08.09.2002)
>
>I stopped the analysis with yace.
>
>Maybe someone with better hardware or better software can find that white is
>winning.
>
>Uri




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