A181277 Number of nX(n+3) binary matrices M with rows in strictly increasing order and rows of M*Mtranspose (mod 2) in strictly decreasing order.

16, 188, 6060, 507052, 115127924, 76961864884

Offset

1,1

Links

Table of n, a(n) for n=1..6.

Example

M and M*Mtranspose (mod 2) for 3X6
..0..1..0..1..0..1......1..1..1
..0..1..1..0..1..0......1..1..0
..1..0..1..1..1..0......1..0..0

Crossrefs

Superdiagonal 3 of A181274.

Sequence in context: A240361 A016292 A231834 * A181269 A004333 A383205

Adjacent sequences: A181274 A181275 A181276 * A181278 A181279 A181280

Keyword

nonn,more

Author

R. H. Hardin, Oct 10 2010

Status

approved