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A223757 Number of nX3 0..3 arrays with rows, antidiagonals and columns unimodal 1
50, 2500, 61733, 916107, 9478535, 74824917, 477860225, 2571238699, 12006271464, 49749360288, 186123469150, 637408917764, 2020521264556, 5982701793264, 16672986760595, 44013068603319, 110650947588800, 266164581427718 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A223762

LINKS

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

FORMULA

Empirical: a(n) = (89/169374965760)*n^18 + (673039/29640619008000)*n^17 + (5753323/10461394944000)*n^16 + (20639/2335132800)*n^15 + (5460977/52306974720)*n^14 + (350675333/373621248000)*n^13 + (34569853/5225472000)*n^12 + (744079211/20118067200)*n^11 + (1214093389/7315660800)*n^10 + (3120210973/5225472000)*n^9 + (1381865894063/804722688000)*n^8 + (2224350329/574801920)*n^7 + (252375235967/37362124800)*n^6 + (1486577243227/163459296000)*n^5 + (2159143550149/217945728000)*n^4 + (154699301/14414400)*n^3 - (959722661/467812800)*n^2 + (50040773/6126120)*n + 1

EXAMPLE

Some solutions for n=3

..1..1..3....1..2..2....0..0..2....1..3..1....0..1..3....3..2..1....0..3..2

..2..2..2....1..3..3....0..3..2....2..1..1....3..3..2....0..3..3....1..3..2

..2..2..0....1..3..3....0..1..3....0..1..3....3..1..0....0..2..2....1..2..1

CROSSREFS

Sequence in context: A267061 A223191 A223807 * A223845 A223871 A223796

Adjacent sequences:  A223754 A223755 A223756 * A223758 A223759 A223760

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 27 2013

STATUS

approved

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Last modified January 22 11:40 EST 2022. Contains 350481 sequences. (Running on oeis4.)