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Subject: Re: A Pragmatic way forward

Author: Heiner Marxen

Date: 13:51:34 02/26/00

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On February 26, 2000 at 14:04:14, guy haworth wrote:

>
>I agree with Eugene's comments.  But to take it further:
>
>Peter Karrer has worked with EN's help to do KQQKQP~ and KQPKQP~, salami-style,
>one pawn-formation at a time, where ~ denotes a variant of chess allowing P=Q
>only.
>
>These tables only required KQQKQQ + available 5-man tables for subgames.
>
>Peter showed that only 0.09% of KQQKQP(d2) positions change value of P=N is
>allowed, and yes, there are positions that change from a win for White to a win
>for Black.

Nearly 1 out of 1100 sound a lot to me.

>Hence, I expect practical o.t.b. players will accept information this near
>perfect 'pro tem'.

Maybe.  I could not accept anything containing any error at all.
When I do problem solving, I consider this to be a mathematically exact
job.  Hence, I cannot accept any approximations: they would cause
incorrect answers, which is unusable (for me).

>Therefore, the way forward is to do KQQQKQQ when a big enough 64-bit

That is a surprise for me: does KQQQKQQ really have any practical impact?
Does that occur in real games more than very very rarely?

Heiner


>architecture machine is available.  It's a factor of 12 smaller than the table
>for KQRNKQR (but that's still 5x bigger than KRNKNN for example) and Eugene's
>index-economies work best with lots of Queens on the board.
>
>In its favour is the lack of symmetry:  you can't see Black lasting that long
>except that Black can capture into the maximal wtm KQQKQQ ending.  So maximal
>btm Black losses could be deeper than maximal wtm Wins.
>
>Once you have KQQQKQQ, you can do KQQQKQP~ as Peter did, ditching a factor of 4
>because of the P but winning a factor of 24 because of the fixed Pan position.
>So that gets you to an ending smaller than KRNKNN which is do-able now.
>
>So KQQQKQQ is the next 'big one':  Guy



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