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A225012 Number of 5 X n 0..1 arrays with rows unimodal and columns nondecreasing. 1
6, 36, 161, 581, 1792, 4900, 12174, 27966, 60172, 122464, 237590, 442118, 793092, 1377174, 2322967, 3817351, 6126818, 9624964, 14827487, 22436251, 33394208, 48953224, 70757132, 100942636, 142261016, 198223936, 273277036, 373005396 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A225010.

Apparently column 6 of A071920. - R. J. Mathar, May 17 2014

LINKS

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

FORMULA

Empirical: a(n) = (1/3628800)*n^10 + (1/80640)*n^9 + (1/3780)*n^8 + (19/5760)*n^7 + (4633/172800)*n^6 + (331/2304)*n^5 + (191249/362880)*n^4 + (24421/20160)*n^3 + (10897/5600)*n^2 + (137/120)*n + 1 = 1 + n*(n+1)* (n^8 + 44*n^7 + 916*n^6 + 11054*n^5 + 86239*n^4 + 435086*n^3 + 1477404*n^2 + 2918376*n + 4142880)/ 3628800.

Empirical: G.f.: -x*(x^2 - 3*x + 3) *(x^2 - 2*x + 2) *(x^2 - x + 1) *(x^4 - 4*x^3 + 5*x^2 - 2*x + 1) / (x-1)^11. - R. J. Mathar, May 17 2014

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A263952 A281394 A225380 * A228458 A203050 A203332

Adjacent sequences:  A225009 A225010 A225011 * A225013 A225014 A225015

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 23 2013

STATUS

approved

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Last modified October 21 04:26 EDT 2019. Contains 328291 sequences. (Running on oeis4.)