OFFSET
0,2
COMMENTS
As in chess, a "play" is an action by a single player, a "move" is two contiguous plays by each opponent.
EXAMPLE
Example: a(2) = 12 since after 2 plays there are 12 legal positions:
-x- -x- -x- -x- -o- x-- x-- x-- x-o xo- o-- ox-
--- --- -o- o-- -x- --- --o -o- --- --- -x- ---
-o- o-- --- --- --- --o --- --- --- --- --- ---
CROSSREFS
KEYWORD
nonn,fini,full
AUTHOR
EXTENSIONS
Additional comments from David W. Wilson, Jun 03 2001
STATUS
approved