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A225013 Number of 6Xn 0..1 arrays with rows unimodal and columns nondecreasing 1
7, 49, 252, 1036, 3612, 11088, 30738, 78354, 186142, 416394, 884236, 1794196, 3497248, 6577474, 11980667, 21201211, 36548573, 61520899, 101320712, 163556776, 259187048, 403770544, 619111172, 935394436, 1393938716, 2050706932 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A225010

LINKS

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

FORMULA

Empirical: a(n) = (1/479001600)*n^12 + (1/7257600)*n^11 + (187/43545600)*n^10 + (13/161280)*n^9 + (14671/14515200)*n^8 + (3043/345600)*n^7 + (2380201/43545600)*n^6 + (347911/1451520)*n^5 + (8129699/10886400)*n^4 + (923183/604800)*n^3 + (913741/415800)*n^2 + (49/40)*n + 1

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

CROSSREFS

Sequence in context: A224150 A094430 A188561 * A228459 A203059 A203383

Adjacent sequences:  A225010 A225011 A225012 * A225014 A225015 A225016

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 23 2013

STATUS

approved

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Last modified November 14 02:19 EST 2019. Contains 329108 sequences. (Running on oeis4.)