A266422 - OEIS

A266422

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

2, 7, 39, 404, 8764, 448649, 59155748, 21325003746, 21901867532457, 66087854484252677, 600640567173169508177

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Diagonal of A266428.

LINKS

EXAMPLE

Some solutions for n=4

..0..0..0..1....0..0..0..0....0..0..1..1....0..0..0..0....0..0..1..1

..0..1..1..1....0..1..1..1....0..1..0..0....0..0..1..1....0..1..0..1

..1..0..1..1....1..0..0..1....1..0..1..1....0..1..0..0....0..1..1..1

..1..1..1..1....1..1..1..0....1..1..0..1....1..0..1..1....1..0..0..1

CROSSREFS

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 29 2015

STATUS

approved