Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: KRRNKRR win in 290: a new record

Author: Yakov Konoval

Date: 00:26:40 10/18/05

Go up one level in this thread


>>
>>For 64-piece tablebases MaxDTC = 1.
>
>more than 32 pieces are illegal positions and I do not claim that this rule is
>always correct but only that there is no reason to think that 7 will be the
>first exception.
>

But theoretically there is the number_of_pieces < 64 with absolute MaxDTC or
MaxDTZ value.
Moreover for 6-man tablebases with pawns MaxDTZ << 243.
And for 6-man tablebases krnknn(243), krbknn(223), and krbkbn(near 190) are
rary exceptions.
For non-standard boards MaxDTC may be really very large.
2 years ago I wrote one program for unusual boards, unusual pieces and unusual
rules. According to this program in knk-ending white always can force stalemate
on 6*N board with speedly increasing Distance_To_Stalemate.

>
>The first exception may be 7 pieces,8 pieces,9 pieces,10 pieces,11 pieces,12
>pieces,13 pieces,...
>

>> I think, that 290-move record may be
>>improved, but there are no position with MaxDTC >= 243*2.

>
>Not all the 7 piece tablebases were investigated so we do not know that there
>are no position with MaxDTC>=243*2
>
>My guess is that MaxDTC>=243*2 and MaxDTZ>=243*2 but we will probably need to
>wait at least few years to see who is right.
>

There are 736 7-man pawnless EGTs in our (with Marc) metric. About 40 of them
are already done. Many of remaining EGTs are not interesting. But calculation
of all 7-man EGTs really may take a few years (or a few hundred computers + a
few weeks). And from these 40 EGTs we already have 5 EGTs with MaxDTC >= 200.

Yakov




This page took 0.02 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.