A162059 Number of n X n symmetric binary arrays with rows, considered as graycode numbers, in nondecreasing order, and no more than 4 ones in any row or column

2, 6, 18, 100, 691, 6729, 78478, 1102775, 17908058, 330070220, 6865933571, 158038101259, 4006358927524, 110885649721312

Offset

1,1

Links

Table of n, a(n) for n=1..14.

Crossrefs

Sequence in context: A028857 A052687 A302546 * A162060 A162061 A162062

Adjacent sequences: A162056 A162057 A162058 * A162060 A162061 A162062

Keyword

nonn

Author

R. H. Hardin Jun 25 2009

Status

approved