Re: computer-go: 5 x 5 perfect play

[Jeffrey Rainy <JRainy@xxxxxxxxxxxx>]

Er... thanks. My other mail about hashing should also read 3^ rather than 2^.

J.

2002.10.15 17:02:48, Don Dailey <drd@xxxxxxxxxxxxxxxxx> wrote:

>
>I think the number of possible positions is  3^25 * 2.   This number
>includes lots of illegal postions.  It may be bigger than this if
>you consider ko states, which could make visually  identical postions
>conceptually different.   
>
>The two is that each "physical" position can have 2 different color
>to move states.   
>
>Don
>
>
>   Date: Tue, 15 Oct 2002 13:29:46 -0700
>   From: Mitchell Timin <timin@xxxxxxxxxxxxxxxxx>
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>
>   Jeffrey Rainy wrote:
>   <snip>
>   > Also, 2^25 is not the actual number of possible 5x5 board positions. On one 
hand,
>   > the capture rule lowers this number a lot. On the other hand, the ko rule 
raises this
>   > number somehow. But that is just nitpicking ;-)
>   > 
>   > Jeff.
>
>   Of what value is the number 2^25?  That doesn't seem relevant to me.  A
>   first estimate of the number of different games is 25!, which is a much
>   bigger number than 2^25.  (Symettry will reduce it, but the capture of
>   large groups will increase it.)
>
>   2^25 is the number of different full boards, with no empty
>   intersections, from all black stones to all white stones. 
>
>   z
>
>   -- 
>   "If we aren't supposed to eat animals, why are they made of meat?"
>
>