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MatPlus.Net Forum Internet and Computing Tablebases with other board sizes

### Tablebases with other board sizes

I know that 4*4 chess (with orthodox figures :-) is *completely* solved.
But why stop? I knew quite a few interesting 4 men,m*n-board problems
that could be solved fastest with a tablebase.
- Can R draw Q if n>8? This might as well be possible.
- Can R beat B if n<8 even with B in the "right" corner? Oh yes, in some cases.
(Did some hand analysis supporting this.)
- Possibly you can show an Excelsior on 9*9 or 10*10 with *just 2wP*!
- Even as small as 4-men fairy tablebases surely will contain some
gold nuggets.
Now, if I were half as old, I would program this myself in a day, but I
am too weary and idle to annoy myself with stalemate branch-off conditions
and other intricacies. :-) Is there somewhere a free adjustable proggie where
you just fix board sizes or piece movement or whatsnot and then you can
DYI tablebase? Hey, even a covers-it-all tablebase pseudocode would save
work tremendously.

Hauke

(2) Posted by Siegfried Hornecker [Wednesday, Dec 21, 2011 18:48]; edited by Siegfried Hornecker [11-12-21]

Marc Bourschutzky has already shown that Queen versus Rook is a theoretical draw on boards with sizes of n*n where n is at least 16. And it is won on smaller boards. See EG 175 special issue.

Is this the end of composition? ;-)

Does the tablebases obey the authors' rights? I didn't look at tablebases but I'm interested in that stuf. Could you help me? :D

QUOTE
I know that 4*4 chess (with orthodox figures :-) is *completely* solved.

Can you share more details about the complete solution of 4x4 chess? My solution is only up to 9 pieces, which is far from complete.

I am curious to explore other board sizes, if I'll have enough energy. Won't be soon though.

BTW, I doubt I could have programmed it in a day, even if I was half as old.

Sorry, Kirill. Of course I screwed up as usual and made a typo
when referring to 3x4 chess.

Hauke

EDIT: The "could have programmed" is mostly rhetoric - but case in
point, I programmed "8 queens problem" on a TI-58 which had a
memory of 239 *steps*. That was around 1977 (I was 16, so you can't
truly call me a computer kid :-)

I computed the 8 queens on an hungarian table-computer EMG 666 with 800 Byte RAM in 1981. Later the RAM was extented to 2 kB, so the predecessor of Gustav solved twomovers. Some months ago I wrote one SQL statement to receive the number of solutions of the N-queens problem.