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A223841 Number of 5Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing 1
6, 36, 149, 471, 1240, 2884, 6159, 12371, 23716, 43790, 78342, 136368, 231677, 385101, 627571, 1004341, 1580713, 2449699, 3742152, 5640008, 8393406, 12342594, 17945687, 25813519, 36753026, 51820812, 72388786, 100224016, 137585227 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 5 of A223838

LINKS

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

FORMULA

Empirical: a(n) = (1/3628800)*n^10 - (1/241920)*n^9 + (17/120960)*n^8 - (1/13440)*n^7 + (3733/172800)*n^6 - (893/11520)*n^5 + (178931/90720)*n^4 - (188123/60480)*n^3 + (504149/25200)*n^2 - (30581/420)*n + 121 for n>4

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A056375 A018214 A181478 * A210322 A056268 A001117

Adjacent sequences:  A223838 A223839 A223840 * A223842 A223843 A223844

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 27 2013

STATUS

approved

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Last modified February 21 14:29 EST 2018. Contains 299414 sequences. (Running on oeis4.)