Author: Robert Hyatt
Date: 17:31:50 12/07/03
Go up one level in this thread
On December 07, 2003 at 15:22:24, Dieter Buerssner wrote:
>On December 07, 2003 at 10:24:48, Uri Blass wrote:
>
>[much snipped]
>>On December 06, 2003 at 18:10:23, Dana Turnmire wrote:
>>
>>>> 4k3/5ppp/8/8/8/8/PPP5/3K4 w - -
>>>>
>>>>{The main variation is } 1. Ke2 Kd7 2. Kf3 Kc6 3. a4 h5 4. c4 f5 5. Kg3 Kb6 6.
>
>>Can you give me a proof that white wins with 1.Ke2 and not with 1.a4?
>
>I don't have any proof (yet?). Also, I think Dana did not say, that no other
>moves than 1. Ke2 will win. I just studied the pos with some backward analysis
>of Yace (I started from variations given by Dana). After Ke2 Kd7 Kf3 I get:
It is absolutely certain that Ke2 wins, any other first move draws. If white
plays anything other than Ke2, then another wrong step can actually lose this.
I think GM Larry Evans explained this years ago in Chess Life. It is not
hard. In fact, it is a lot like the game "NIM" if you know how that is
played. After the first white move, Ke2, any further white move is a
direct response to black, to keep the zugzwang alive later.
>
>
> 95112158 1:40.0 -4.04 21. 2...f5 3.Kf4 g6 4.a4 h6 5.a5 h5 6.Kg5 Kc6 7.c4
> Kc7 8.b4 Kb8 9.c5 Kb7 10.b5 Kb8 11.c6 Kc7
> 12.Kxg6 h4 {-80}
> 96211359 1:41.5 -4.44 22-- 2...f5 3.Kf4 g6 4.a4 h6 5.a5 h5 6.Kg5 Kc6 7.c4
> Kc7 8.c5 Kd8 9.b4 Ke8 10.b5 h4 11.Kxh4 Kd8H
> 12.a6H Kc7H 13.Kg5H Kc8H 14.Kxg6H {HT} {-160}
> 131949723 2:21.5 -4.95 22t 2...f5 3.Kf4 g6 4.a4 h6 5.a5 h5 6.Kg5 Kc6 7.c4
> Kc7 8.c5 Kb8 9.b3 Kc8 10.a6 h4H 11.Kxh4H Kb8H
> 12.c6H g5+H 13.Kxg5H {HT} {-160}
> 267226972 5:08.0 -4.94 22t+ 2...Kc6 3.c4 Kc5 4.b4+ Kxb4 5.a4 Kxa4 6.c5 Ka5
> 7.c6 Ka6 8.Kg2 f5 9.Kh3 g6 10.Kg3 h5 11.Kf3 h4H
> 12.Ke2H g5H 13.Kd1H Ka7H {HT} {160}
> 314686997 6:00.7 -4.40 22t 2...Kc6 3.a4 g6 4.a5H {HT} {0}
> 314686997 6:00.7 -4.40 22. 2...Kc6 3.a4 g6 4.a5 {HT} {0}
> 393958788 7:48.2 -4.40 23t 2...Kc6 3.a4 g6 4.a5H {HT} {0}
>
>PVs shown don't mean too much (I might have "teached" the engine, that more
>obvious defences fail, already). Also, -4.4 is not a proof (mate score should
>be). But I was too lazy, to get higher scores (but I think, it will be
>possible). I am aware, that my engine can show -4.4 in drawn pawn endgames, but
>in this position, I think the probability is very low. I have the engine now in
>a state, where it easily should win after any defence after 1...Kd7. Feel free
>to suggest one.
>
>I used a version of my engine, that accesses the KPPKP TBs from RAM until the
>deepest qsearch nodes. I think, this can be of some advantage in such an
>analysis.
>
>Regards,
>Dieter
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.