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A351157
Number of symmetric 0-1 matrices with zero main diagonal where rows are sorted lexicographically and row sums are nondecreasing.
2
1, 2, 4, 11, 33, 145, 839, 7449
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OFFSET
1,2
LINKS
Table of n, a(n) for n=1..8.
CROSSREFS
Cf. A016121
Sequence in context: A123416 A123406 A123453 * A123459 A123426 A277204
Adjacent sequences: A351154 A351155 A351156 * A351158 A351159 A351160
KEYWORD
nonn,hard,more
AUTHOR
Max Alekseyev, Feb 02 2022
STATUS
approved

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Last modified October 21 00:05 EDT 2024. Contains 376963 sequences.
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