A223635 Number of nX6 0..1 arrays with rows, antidiagonals and columns unimodal

22, 484, 5699, 42109, 230619, 1026377, 3907140, 13135511, 39889555, 111242770, 288488044, 702553878, 1619299148, 3555008655, 7473337157, 15110365462, 29495673113, 55765989646, 102405932407, 183099750019, 319441371676

Offset

1,1

Comments

Column 6 of A223637

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (271/5443200)*n^12 - (10327/9979200)*n^11 + (61997/2177280)*n^10 - (21923/80640)*n^9 + (417761/1814400)*n^8 + (37222841/604800)*n^7 - (2521405483/2177280)*n^6 + (8668581613/725760)*n^5 - (414044081579/5443200)*n^4 + (88564150211/302400)*n^3 - (17419930607/30240)*n^2 + (542846047/3080)*n + 850576 for n>8

Example

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

Crossrefs

Sequence in context: A207744 A207721 A223737 * A223720 A223667 A223826

Adjacent sequences: A223632 A223633 A223634 * A223636 A223637 A223638

Keyword

nonn

Author

R. H. Hardin Mar 24 2013

Status

approved