A266541 Number of n X n binary arrays with rows and columns lexicographically nondecreasing and row and column sums nonincreasing.

2, 3, 5, 12, 36, 176, 1688, 48167, 4283651

Offset

1,1

Comments

Diagonal of A266547.

Links

Table of n, a(n) for n=1..9.

Example

Some solutions for n=6
..0..0..0..0..1..1....0..0..1..1..1..1....0..1..1..1..1..1....0..1..1..1..1..1
..0..0..1..1..0..0....0..1..0..0..1..1....1..0..0..1..1..1....1..0..0..1..1..1
..0..1..0..0..0..0....0..1..0..0..1..1....1..0..1..0..0..1....1..0..1..0..1..1
..1..0..0..0..0..0....1..0..1..1..0..0....1..1..0..0..1..0....1..1..0..1..0..0
..1..0..0..0..0..0....1..0..1..1..0..0....1..1..0..1..0..0....1..1..1..0..0..0
..1..0..0..0..0..0....1..1..0..0..0..0....1..1..1..0..0..0....1..1..1..0..0..0

Crossrefs

Cf. A266547.

Sequence in context: A306038 A008323 A000997 * A301929 A107475 A108225

Adjacent sequences: A266538 A266539 A266540 * A266542 A266543 A266544

Keyword

nonn

Author

R. H. Hardin, Dec 31 2015

Status

approved