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Subject: Re: With Diagram

Author: Robert Hyatt

Date: 12:43:00 12/08/03

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On December 08, 2003 at 13:34:55, Dieter Buerssner wrote:

>On December 07, 2003 at 20:31:50, Robert Hyatt wrote:
>
>>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.
>
>Yace thinks, Ke1 is also winning. After the backwards analysis, I got a score >
>3 for 1. Ke2.
>
>1909477488 44:10.4  -2.88 27t  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 f6 5.c4 f5+ 6.Kh3
>                               Kd8 7.a5 f4 8.Kg4 Kc8 9.c5 Kb7H 10.b4H h3H
>                               11.Kxh3H f3H 12.b5H Kc7H 13.a6H f2H 14.b6+H
>                               {HT} {-80}
>2404355953 58:02.7  -2.88 27.  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 f6 5.c4 f5+ 6.Kh3
>                               Kd8 7.a5 f4 8.Kg4 Kc8 9.c5 Kb7 10.b4 h3 11.Kxh3
>                               f3 12.b5 Kc7 13.a6 f2 14.b6+ {HT} {-80}
>3317357787 1:24:56  -2.96 28t  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 Ke7 5.c4 f5+
>                               6.Kh3H Kd8H 7.a5H f4H 8.Kg4H Kc8H {HT} {0}
>3829004430 1:46:22  -2.96 28.  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 Ke7 5.c4 f5+
>                               6.Kh3 Kd8 7.a5 f4 8.Kg4 Kc8 {HT} {0}
>4138909235 1:58:08  -3.36 29-- 1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 Ke7 5.c4 f5+
>                               6.Kh3 Kd8 7.a5 f4 8.Kg4 Kc8 9.c5 Kb7 10.b4 h3
>                               11.Kxh3 f3 12.Kh2 f2 13.a6+ Kb8 14.a7+ Kc7
>                               15.Kg2 f1=R 16.a8=Q g4 {-581}
>1605579668 2:50:43  -3.45 29t  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 Ke7 5.c4 f5+
>                               6.Kh3 Kd8 7.a5 f4 8.Kg4 Kc8 9.c5 Kb7 10.b4 h3
>                               11.Kxh3 {HT} {-80}
>2589083571 3:25:23  -3.45 29.  1...h5 2.Kf3 h4 3.Kg4 g5 4.a4 Ke7 5.c4 f5+
>                               6.Kh3 Kd8 7.a5 f4 8.Kg4 Kc8 9.c5 Kb7 10.b4 h3
>                               11.Kxh3 {HT} {-80}
>2662304056 5:53:41  -3.84 30t  1...h5 2.Kf3 Kd7 3.a4 g5 4.a5H Kc6H 5.Kg3H f5H
>                               6.c4H h4+H 7.Kh3H Kc7H 8.c5H Kb7H 9.b4H g4+H
>                               10.Kxh4H g3H 11.Kxg3H Kc7H 12.Kf4H {HT} {-160}
>
>Then I started another search at the root (all the previous analysis is
>available inside the search) with 1.Ke2 disabled and I got:
>
>  19833211  23.087   0.97 23++ 1.a4 h5 2.Ke2 f5 3.Kf3 h4 4.a5 h3 5.c4 f4 6.a6
>                               Kf7 7.a7 g6 8.a8=Q Kg7
>  47251798  53.794   1.60 23t  1.a4 h5 2.Ke2 f5 3.Kf3 h4 4.a5 Kd7 5.c4 Kc8
>                               6.Kg2 f4 7.c5 Kb8 8.b4 g6 9.a6 Ka7 10.b5 g5H
>                               11.Kh3H f3H 12.c6H f2H 13.Kg2H {0}
> 112048925  2:09.3   1.61 23t+ 1.Ke1 h5 2.Kf2 Kd7 3.c4 g5 4.Kg2 h4 5.Kh3 g4+H
>                               6.Kxg4H h3H 7.Kxh3H f6H 8.a4H f5H 9.a5H Kc7H
>                               {HT} {160}
> 117978991  2:15.5   1.97 23++ 1.Ke1 h5 2.Kf2 Kd7 3.c4 g5 4.Kg2 h4 5.Kh3 g4+
>                               6.Kxg4 h3 7.Kxh3 f6 8.a4 f5 9.a5 Kd8 10.a6 Ke7
>                               11.a7 Kd7 12.a8=Q f4
> 192766112  3:37.7   3.12 23t  1.Ke1 Kd7 2.a4 g5 3.Kf2 Kc7 4.a5 f5 5.c4 Kb8
>                               6.c5 h6 7.Kg3 Kb7 8.b4 g4 9.Kf4 Kb8 10.a6 Ka7
>                               {HT} {0}
> 193308497  3:38.3   3.12 23.  1.Ke1 Kd7 2.a4 g5 3.Kf2 Kc7 4.a5 f5 5.c4 Kb8
>                               6.c5 h6 7.Kg3 Kb7 8.b4 g4 9.Kf4 Kb8 10.a6 Ka7
>                               {HT} {0}
> 266445981  4:59.3   2.72 24-- 1.Ke1 Kd7 2.a4 Kc7 3.Kf2 f5 4.c4 g5 5.b4 h5
>                               6.a5 h4 7.b5 h3 8.Ke3 g4 9.a6 h2 10.a7 h1=Q
>                               11.a8=R
> 325097970  6:02.6   2.70 24t  1.Ke1 Kd7 2.a4 Kc7 3.Kf2 f5 4.b4H Kb7H 5.a5H
>                               Ka7H 6.b5H h5H 7.Kg3H Ka8H 8.a6H Kb8H 9.c4H
>                               {HT} {0}
> 372025908  6:55.1   2.70 24.  1.Ke1 Kd7 2.a4 Kc7 3.Kf2 f5 4.b4 Kb7 5.a5 Ka7
>                               6.b5 h5 7.Kg3 Ka8 8.a6 Kb8 9.c4 {HT} {0}
> 392424500  7:19.8   3.10 25++ 1.Ke1 Kd7 2.a4 Kc7 3.Kf2 f5 4.b4 Kb7 5.a5 Ka7
>                               6.b5 h5 7.Kg3 Kb7 8.c4 Kb8 9.c5 h4+ 10.Kxh4 g5+
>                               11.Kxg5 Ka7 12.c6 f4 13.Kxf4 {240}
> 524250186  9:48.3   3.79 25t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 f4 5.Kf3 Kc8
>                               6.c4H Kb7H 7.c5H Ka7H 8.c6H Kb8H 9.a6H {HT} {0}
> 591703239 11:04.8   3.79 25.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 f4 5.Kf3 Kc8
>                               6.c4 Kb7 7.c5 Ka7 8.c6 Kb8 9.a6 {HT} {0}
> 832810222 15:50.7   3.47 26t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 f4 5.Kf3 Kc8
>                               6.c4 Kb7 7.c5 Ka7 8.c6 h5 9.b4 Kb8 10.b5 Kc7
>                               11.a6 g4+ 12.Kxf4 Kb6H {HT} {80}
> 970737909 18:35.6   3.47 26.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 f4 5.Kf3 Kc8
>                               6.c4 Kb7 7.c5 Ka7 8.c6 h5 9.b4 Kb8 10.b5 Kc7
>                               11.a6 g4+ 12.Kxf4 Kb6 {HT} {80}
>1330904308 26:05.4   3.46 27t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 f4
>                               6.Kf3 Kb7 7.c5 Ka7H 8.c6H h5H 9.b3H h4H 10.Kg4H
>                               {HT} {0}
>1589539665 31:22.0   3.46 27.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 f4
>                               6.Kf3 Kb7 7.c5 Ka7 8.c6 h5 9.b3 h4 10.Kg4 {HT}
>                               {0}
>2247748524 46:24.8   3.46 28t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 f4
>                               6.Kf3 Kb7 7.c5 Kb8 8.b4 h5 9.a6 Ka7 10.b5 h4
>                               11.c6 Kb6 12.Kg2 {HT} {0}
>2725338622 57:01.6   3.46 28.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 f4
>                               6.Kf3 Kb7 7.c5 Kb8 8.b4 h5 9.a6 Ka7 10.b5 h4
>                               11.c6 Kb6 12.Kg2 {HT} {0}
>3868805732 1:26:36   3.50 29t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 Kb7
>                               6.c5 f4 7.Kf3 Kb8 8.b4H {HT} {0}
> 415491473 1:47:17   3.50 29.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 Kb7
>                               6.c5 f4 7.Kf3 Kb8 8.b4 {HT} {0}
>2665944834 3:01:28   3.66 30t  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 Kb7
>                               6.c5 f4 7.Kf3 Kb8 8.b4 h5 9.a6 h4 10.Kg4 f3
>                               11.Kxf3 Ka7 12.b5 h3 {HT} {80}
>  93037799 3:49:50   3.66 30.  1.Ke1 Kd7 2.a4 f5 3.Kf2 g5 4.a5 Kc6 5.c4 Kb7
>                               6.c5 f4 7.Kf3 Kb8 8.b4 h5 9.a6 h4 10.Kg4 f3
>                               11.Kxf3 Ka7 12.b5 h3 {HT} {80}
>
>Unfortunately, there was a power cut in the house then (I wanted to let it run
>for longer, and also wanted to try a4; but when I came back the computer was
>switched off, also my electric clock was wrong ...). Now all the analysis is
>lost.
>
>Above there is also the interesting score of 1.6 for a4. With a normal search
>(without the backward analysis), I get only drawish score for a4 at depth 23. So
>it seems the search has found some forced transpositions from 1.a4 to other
>analysed variations after 1. Ke2, that seem good for white.
>
>Regards,
>Dieter


As I said, I _believe_ it has been exhaustively proven that Ke2
wins, everything else draws.  You might ask someone on ICC with a
very high "wild rating" about this game.  There are several IM/GM
players that play it perfectly and can tell you what is wrong
about any move you play.  But for the record, this is a win by _one_
tempo.  If you do anything to lose that tempo, it turns into a draw
instantly.  Lose one more and it becomes a loss.  After Ke2, the
plan is to play a4-5-6 and c4-5-6 without moving the b-pawn _ever_
unless it is needed for a tempo after the off-side pawns are
immobolized.  It is amazing how the black king can't stop the two
white pawns from advancing if it _has_ to move.  So white's plan is
to advance those pawns, meanwhile watching black's off-side moves.

For every black off-side move, white counters so that black gets zugged
on the offside first, then gets zugged on the queenside next.  As I said,
it is a "nim-like" game with a finite solution that is pretty easy to see
once you understand it.  a4 certainly won't win.  Ke1 won't either.

The point for Ke2 is that you are moving toward two goals at the same time.
Closer to your own queen-side advancement, and closer to the king-side of your
opponent, and one rank farther up the board as if you stick on the first rank
you lose when the two black pawns come up the board  You have to be able to
stop them before they both reach the third rank or you die.  Fiddling around
on the first rank won't do.



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