A223622 - OEIS

A223622

Number of nX4 0..1 arrays with row sums nondecreasing and column sums unimodal

11, 98, 751, 5303, 35413, 228401, 1437511, 8898472, 54437857, 330381980, 1993659689, 11985196268, 71858499637, 430123654878, 2571650477297, 15366254287831, 91781204372957, 548141570513665, 3273511579537537

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

OFFSET

1,1

COMMENTS

Column 4 of A223625

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..28

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A016140 A138930 A106136 * A130886 A239486 A015671

Adjacent sequences: A223619 A223620 A223621 * A223623 A223624 A223625

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 24 2013

STATUS

approved