A183411 Number of nX4 binary arrays with each sum of a(1..i,1..j) no greater than i*j/2 and rows and columns in nondecreasing order

3, 15, 75, 380, 1518, 6450, 20066, 69431, 178672, 525241, 1180351, 3058649, 6214736, 14582583, 27430148, 59415592, 105109158, 213169589, 358764046, 688540612, 1111600419, 2035522230, 3172787043, 5579376657, 8437795792, 14323523879

Offset

1,1

Comments

Column 4 of A183413

Links

R. H. Hardin, Table of n, a(n) for n = 1..84

Example

Some solutions for 6X4
..0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0
..0..0..1..0....0..0..1..1....0..0..1..1....0..0..0..1....0..0..0..0
..0..1..0..1....0..1..0..1....0..1..0..1....0..1..1..1....0..0..0..1
..1..0..0..0....0..1..1..1....0..1..0..1....0..1..1..1....0..1..1..1
..1..0..0..0....1..0..0..1....1..0..0..0....1..0..1..0....0..1..1..1
..1..1..1..1....1..1..0..1....1..0..0..1....1..1..1..0....1..1..1..1

Crossrefs

Sequence in context: A236579 A005053 A329764 * A136778 A300665 A278398

Adjacent sequences: A183408 A183409 A183410 * A183412 A183413 A183414

Keyword

nonn

Author

R. H. Hardin Jan 04 2011

Status

approved