The chess position with the most possible legal moves?

[Terry McCracken]

Have a look of the bottom of following web-site:

http://www.10x8.net/chess/Zahlen.html

Malicious Website! You've Been Warned! Enter at Own Risk!

[bnst]

Here is a link to a 64-bit compile and a new 32-bit compile. The performance seems to be the same as the old one though:
https://drive.google.com/file/d/0B3_wqC ... sp=sharing

This is a very old program with a rather obscure interface, but to get all the statistics run it like this: joined.exe -q -v126 <input file>
It was the beginning of a chess playing program that never got finished though at one point it managed to beat me

Regards
Andreas

[zullil]

1) Positions where no promotions have taken place yet (but one is possible on the move, with underpromotions being different moves).

144 moves, Dr. Jeno Ban, 1960
[d]n1r1r1b1/1P1P1P1P/1Q6/3NBNK1/R7/4p1p1/3PBPkP/2R5 b - - 0 1

Alex

Should be White to move:

[D]n1r1r1b1/1P1P1P1P/1Q6/3NBNK1/R7/4p1p1/3PBPkP/2R5 w - - 0 1

144 is correct, at least according to my new (legal) move generator.

Code: Select all

ProcyonLeo: ~/Documents/Chess/Kirby] ./generator 
num_moves = 144.

[Brunetti]

Should be White to move [...] 144 is correct, at least according to my new (legal) move generator.

Actually I didn't know who has the move, my FEN was limited to board, and it seems I didn't look a the position I just wrote a random color to let the forum accept and display it.

Alex

[zullil]

Should be White to move [...] 144 is correct, at least according to my new (legal) move generator.

Actually I didn't know who has the move, my FEN was limited to board, and it seems I didn't look a the position I just wrote a random color to let the forum accept and display it.

Alex

I only noticed when I entered your FEN (also without really looking) and my generator gave 25 moves instead of 144.