Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: number of pawn positions in chess...

Author: Timothy J. Frohlick

Date: 23:59:23 01/12/00

Go up one level in this thread


>
>Dan,
>
>I don't think the "a" pawn is going to end up on the e,f,g,or h files and don't
>forget that the black pawns prevent occupation except by capture of the white
>pawns. You also have to account for en passant which usually occurs only once
>per game at most.
>
[D]8/pppppppp/8/8/8/8/PPPPPPPP/8 w
>
>So the progression should be 20x19x18....etc and be extended out for a total of
>sixteen pawns.  20x19x18x17x16x15x14x13x12x11x10x9x8x7x6x5x4= 8.109673360589e+17
>which is a pretty big number of possibilities.  Even if we limited  the combos
>to (Whitemoves x 10x9x8x7x6x5x4x3) + (Blackmoves x 10x9x8x7x6x5x4x3)=3,628,800
>possibilities you can see that we will not run out of moves soon.  If the
>average game is 75 moves or 150 ply we would have to play at least 24,192 games
>to exhaust the possibilities.  Again, since not every move is a pawn move we
>would have a variable number of pawn moves and positions.  So if only one
>quarter of our moves are pawn moves we would have to play about 100,000 games to
>come to a correct estimation of the number of different pawn structures.
>
>This is just my opinion and is probably wrong.
>
>Tim Frohlick



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.