

A224192


Number of 5Xn 0..2 arrays with rows unimodal and columns nondecreasing


1



21, 441, 5852, 55438, 408222, 2469182, 12741432, 57644194, 233385140, 859145920, 2912085006, 9181289736, 27151590510, 75840301088, 201262238349, 509972027785, 1239109721281, 2897739996141, 6543276177902, 14306873805792, 30366198279340
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OFFSET

1,1


COMMENTS

Row 5 of A224190


LINKS

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


FORMULA

Empirical: a(n) = (1/1379196149760000)*n^20 + (1/12538146816000)*n^19 + (467/101624979456000)*n^18 + (223/1302884352000)*n^17 + (9641/2134978560000)*n^16 + (44237/498161664000)*n^15 + (115879/86102016000)*n^14 + (24029081/1494484992000)*n^13 + (623419/4055040000)*n^12 + (18199033/15328051200)*n^11 + (3421967251/459841536000)*n^10 + (263944057/6967296000)*n^9 + (8168948285977/52306974720000)*n^8 + (193145489021/373621248000)*n^7 + (507138710909/373621248000)*n^6 + (13262560631/4790016000)*n^5 + (3783062210933/882161280000)*n^4 + (108121887773/22054032000)*n^3 + (27314271011/6518191680)*n^2 + (14737223/8314020)*n + 1


EXAMPLE

Some solutions for n=3
..1..2..0....0..1..0....0..1..0....0..0..0....0..2..1....0..0..2....1..1..0
..1..2..0....1..1..1....0..1..0....0..0..0....0..2..1....0..1..2....1..1..0
..2..2..0....2..1..1....0..1..2....1..2..1....0..2..1....1..2..2....2..2..0
..2..2..1....2..2..1....0..2..2....1..2..1....1..2..2....1..2..2....2..2..1
..2..2..2....2..2..2....1..2..2....2..2..2....1..2..2....2..2..2....2..2..1


CROSSREFS

Sequence in context: A188770 A223922 A224350 * A207184 A189060 A224009
Adjacent sequences: A224189 A224190 A224191 * A224193 A224194 A224195


KEYWORD

nonn


AUTHOR

R. H. Hardin Apr 01 2013


STATUS

approved



