A266545 Number of nX6 binary arrays with rows and columns lexicographically nondecreasing and row and column sums nonincreasing.

2, 5, 11, 27, 58, 176, 366, 1062, 2571, 7345, 17540, 47970, 109375, 272134, 595031, 1359839, 2827311, 6072251, 12027150, 24388681, 46416427, 89575530, 164016985, 303788687, 537614351, 959313275, 1647205384

Offset

1,1

Comments

Column 6 of A266547.

Links

Table of n, a(n) for n=1..27.

Example

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

Crossrefs

Cf. A266547.

Sequence in context: A067922 A212567 A339755 * A095975 A006652 A340314

Adjacent sequences: A266542 A266543 A266544 * A266546 A266547 A266548

Keyword

nonn

Author

R. H. Hardin, Dec 31 2015

Status

approved