A162094 Number of n X n symmetric binary arrays with rows, considered as binary numbers, in strictly increasing order, and no more than 4 ones in any row.

2, 3, 9, 48, 397, 4046, 50562, 725875, 11870670, 219522591, 4530707851, 103448006539, 2595528068368, 71042542549939

Offset

1,1

Links

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

Crossrefs

Sequence in context: A219673 A012972 A316916 * A162095 A162096 A162097

Adjacent sequences: A162091 A162092 A162093 * A162095 A162096 A162097

Keyword

nonn

Author

R. H. Hardin, Jun 25 2009

Status

approved