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A351127
Number of polyominoes with n cells with maximal symmetry and center of rotation about the center of a square.
5
1, 0, 0, 0, 1, 0, 0, 1, 2, 0, 0, 1, 2, 0, 0, 4, 4, 0, 0, 7, 7, 0, 0, 16, 11, 0, 0, 29, 20, 0, 0, 67, 36, 0, 0, 119, 65, 0, 0, 264, 117, 0, 0, 478, 216, 0, 0, 1043, 396, 0, 0, 1910, 736, 0, 0, 4116, 1369, 0, 0, 7592, 2558, 0, 0, 16201, 4787, 0, 0, 30114, 9006
OFFSET
1,9
COMMENTS
The sequence enumerates a subset of the polyominoes of maximal symmetry enumerated by A142886.
FORMULA
For n multiple of 4, a(n) = A142886(n) - A346800(n/4); otherwise a(n) = A142886(n).
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
John Mason, Feb 02 2022
STATUS
approved