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A223618 Number of nX6 0..1 arrays with rows and columns unimodal 1
22, 484, 6504, 57238, 367216, 1856100, 7795951, 28248007, 90732638, 263650284, 703980614, 1748547620, 4079672416, 9012596316, 18975151965, 38281575869, 74344179766, 139521245076, 253869738212, 449160402594, 774624001120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A223620

LINKS

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

FORMULA

Empirical: a(n) = (271/5443200)*n^12 + (2327/3326400)*n^11 + (39107/5443200)*n^10 + (1579/36288)*n^9 + (52553/259200)*n^8 + (192371/302400)*n^7 + (8636441/5443200)*n^6 + (56113/20160)*n^5 + (2901677/680400)*n^4 + (523927/113400)*n^3 + (23969/5400)*n^2 + (33487/13860)*n + 1

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A223720 A223667 A223826 * A223678 A223784 A223970

Adjacent sequences:  A223615 A223616 A223617 * A223619 A223620 A223621

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 24 2013

STATUS

approved

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Last modified January 25 07:52 EST 2020. Contains 331241 sequences. (Running on oeis4.)