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A263677
Irregular table read by rows, n >= 1, k >= 0: T(n,k) is the number of binary symmetric n X n matrices with k holes that are squares, where the axes of symmetry are horizontal and vertical.
1
1, 1, 3, 1, 3, 1, 28, 15, 11, 0, 6, 3, 30, 16, 0, 0, 3, 3
OFFSET
1,3
COMMENTS
Inspired by A258643 but the axes of symmetry are the same as in A262742. The mirror patterns and nonsquare holes are excluded.
EXAMPLE
Irregular table begins:
n\k 0 1 2 3 4 5 ...
1 1
2 1
3 3 1
4 3 1
5 28 15 11 0 6 3
6 30 16 0 0 3 3
...
CROSSREFS
Sequence in context: A262940 A278601 A281038 * A099906 A262026 A270390
KEYWORD
nonn,tabf,more
AUTHOR
Kival Ngaokrajang, Oct 23 2015
STATUS
approved