A266360 Number of nX6 binary arrays with rows and columns lexicographically nondecreasing and row and column sums nondecreasing.

7, 50, 337, 2278, 14921, 93085, 541207, 2909244, 14424728, 66153106, 281891001, 1122295653, 4197508078, 14825103751, 49679349839, 158631629088, 484502593301, 1420310391763

Offset

1,1

Comments

Column 6 of A266362.

Links

Table of n, a(n) for n=1..18.

Example

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

Crossrefs

Cf. A266362.

Sequence in context: A293801 A227676 A278875 * A288787 A033117 A096882

Adjacent sequences: A266357 A266358 A266359 * A266361 A266362 A266363

Keyword

nonn

Author

R. H. Hardin, Dec 28 2015

Status

approved