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A356049
Symmetric array read by antidiagonals: T(n,k) is the number of legal positions in Go on an n X k board.
2
1, 5, 5, 15, 57, 15, 41, 489, 489, 41, 113, 4125, 12675, 4125, 113, 313, 35117, 321689, 321689, 35117, 313, 867, 299681, 8180343, 24318165, 8180343, 299681, 867, 2401, 2557605, 208144601, 1840058693, 1840058693, 208144601, 2557605, 2401
OFFSET
1,2
COMMENTS
A Go position is a grid containing white and black stones with the condition that every orthogonally connected group of stones of a single color has liberties, i.e., is orthogonally adjacent to an empty cell.
EXAMPLE
Array begins:
1, 5, 15, 41, ...
5, 57, 489, ...
15, 489, ...
41, ...
...
T(3,1) = 15 from
... ..w ..b .w. .ww .b. .bb w.. w.w w.b ww. b.. b.w b.b bb.
CROSSREFS
Columns (or rows) give: A102620, A266278.
Main diagonal gives A094777.
This as triangle gives A356134.
Sequence in context: A275016 A189316 A370236 * A154232 A194615 A195465
KEYWORD
nonn,tabl
AUTHOR
Douglas Boffey, Jul 24 2022
STATUS
approved