A139676 Number of n X n symmetric binary matrices with all row sums 9.

1, 9496, 108306280, 1322299270600

Offset

9,2

Links

Table of n, a(n) for n=9..12.

Crossrefs

Sequence in context: A204961 A237104 A156402 * A291209 A235424 A235420

Adjacent sequences: A139673 A139674 A139675 * A139677 A139678 A139679

Keyword

nonn

Author

R. H. Hardin, Jun 12 2008

Status

approved