A267239 Number of n X n binary arrays with row sums nondecreasing and columns lexicographically nondecreasing.

2, 7, 42, 567, 20040, 2093467, 683027146, 723576702570, 2549735632656528, 30465608408449993885, 1250919952257037350168062, 178764247753852768666003981113, 89752660973687899647122735126286078

Offset: 1

Author

R. H. Hardin, Jan 12 2016

Keywords

• nonn

Comments

Diagonal of A267245.

Examples

			Some solutions for n=4
..0..0..0..1....0..0..0..1....0..0..1..1....0..0..0..1....0..0..0..1
..0..1..1..0....0..0..0..1....0..1..0..1....0..0..1..1....0..0..1..1
..1..0..1..0....0..0..1..1....1..1..0..0....0..1..0..1....1..1..1..0
..1..1..1..1....1..1..1..0....1..1..0..0....1..1..1..0....1..1..0..1
		

Crossrefs

Cf. A267245.