Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Where does the 10^50 upper bound for chess positions come from?

Author: Uri Blass

Date: 04:10:27 05/10/01

Go up one level in this thread


On May 10, 2001 at 05:31:05, Graham Laight wrote:

>I apologise if you've already explained how it's calculated - but I missed it.
>
>Would you mind explaining in a straightforward way how you calculated this upper
>bound, please?

I calculated by a program that counted for every material configuration the
number of pseudo legal positions with the same material configuration.

The program calculated the sum of all the numbers in order to find an upper
bound for the number of legal positions when you do not consider side to
move,castling and the enpassant rule.

It found the following number:

3.7010630121207222927827147741452119115968e46

It needed many minutes to find the number because it had to calculate the sum of
a lot of numbers.

I remember that someone found a smaller number by finding that part of the
structures are illegal structures but the difference was not big and the smaller
number was still more than 10^46.

You can multiply the number by 2 if you consider side to move and even increase
it if you consider castling and the en passant rule but it is clearly less than
10^50.


 >
>It intuitively sounds right to me - I'd just like to know how you calculated it!
>
>By the way - as I've said before (excuse the repetition!), my own view on the
>solving of chess is that, as the standard of chess continues to rise, the
>proportion of draws will also continue to rise. Eventually, you'll get to a
>point where almost all games are drawn. At this point, people will
>(pragmatically) conclude that chess is a draw - and the interest in continuing
>to drive up the standards of chess programs will disappear.
>
>-g

I agree

Uri



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.