A162116 Number of n X n symmetric binary arrays with rows, considered as graycode numbers, in strictly increasing order, and no more than 8 ones in any row or column

2, 4, 9, 56, 499, 8000, 207554, 9382078, 723818669, 93919689474, 19191447316594, 5833792312541241

Offset

1,1

Links

Table of n, a(n) for n=1..12.

Crossrefs

Sequence in context: A162113 A162114 A162115 * A162117 A162109 A271553

Adjacent sequences: A162113 A162114 A162115 * A162117 A162118 A162119

Keyword

nonn

Author

R. H. Hardin Jun 25 2009

Status

approved