A139679 Number of n X n symmetric binary matrices with no row sum greater than 3.

1, 2, 8, 64, 809, 13846, 301262, 8035168, 255780779, 9519891214, 407613033836, 19816627136912, 1082142442901863, 65776576008442274, 4416031241930248774, 325289604104049686096, 26137255635911145802777, 2279186202842678350137218, 214713550195887533572753024

Offset: 0

Author

R. H. Hardin, Jun 13 2008

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 0..100

Crossrefs

Column k=3 of A334548.

Extensions

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