A139681 Number of n X n symmetric binary matrices with no row sum greater than 5.

1, 2, 8, 64, 1024, 32768, 1914733, 178499118, 23973965155, 4356864886906, 1028823851939030, 306635655405986312, 112789704243814005142, 50281311185009713150048, 26760450115727957945767409, 16787646103442094018698106106, 12278130772483524854754380090307

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..30

Crossrefs

Column k=5 of A334548.

Sequence in context: A084281 A153548 A153576 * A084282 A139682 A139683

Adjacent sequences: A139678 A139679 A139680 * A139682 A139683 A139684

Keyword

nonn

Author

R. H. Hardin, Jun 13 2008

Extensions

Terms a(13) and beyond from Andrew Howroyd, May 08 2020

Status

approved