A188391 Number of (7*n) X 7 binary arrays with rows in nonincreasing order and n ones in every column.

877, 624889, 238773109, 55643064708, 8738543204786, 992649275638900, 85864898797026630, 5878897478976883089, 328290088245117576091, 15312799057782368782624, 608266461487720680703265, 20908600183730320082374280

Offset

1,1

Links

Table of n, a(n) for n=1..12.

Example

Some solutions for 14 X 7:
..1..0..0..0..0..0..0....1..0..0..0..1..0..1....1..0..0..1..0..0..1
..1..0..0..0..0..0..0....1..0..0..0..1..0..0....1..0..0..0..0..0..0
..0..1..1..0..0..0..0....0..1..0..1..0..0..0....0..1..0..0..0..0..0
..0..1..0..0..0..0..1....0..1..0..0..0..0..0....0..1..0..0..0..0..0
..0..0..1..0..0..0..1....0..0..1..1..0..1..0....0..0..1..1..0..0..1
..0..0..0..1..1..1..0....0..0..1..0..0..0..0....0..0..1..0..0..0..0
..0..0..0..1..0..0..0....0..0..0..0..0..1..0....0..0..0..0..1..1..0
..0..0..0..0..1..1..0....0..0..0..0..0..0..1....0..0..0..0..1..1..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....0..0..0..0..0..0..0

Crossrefs

Column 7 of A188392.

Sequence in context: A255947 A048791 A273657 * A209464 A209526 A208307

Adjacent sequences: A188388 A188389 A188390 * A188392 A188393 A188394

Keyword

nonn

Author

R. H. Hardin, Mar 30 2011

Extensions

a(7)-a(12) from Andrew Howroyd, May 17 2020

Status

approved