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A224192 Number of 5Xn 0..2 arrays with rows unimodal and columns nondecreasing 1

%I

%S 21,441,5852,55438,408222,2469182,12741432,57644194,233385140,

%T 859145920,2912085006,9181289736,27151590510,75840301088,201262238349,

%U 509972027785,1239109721281,2897739996141,6543276177902,14306873805792,30366198279340

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

%C Row 5 of A224190

%H R. H. Hardin, <a href="/A224192/b224192.txt">Table of n, a(n) for n = 1..210</a>

%F 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

%e Some solutions for n=3

%e ..1..2..0....0..1..0....0..1..0....0..0..0....0..2..1....0..0..2....1..1..0

%e ..1..2..0....1..1..1....0..1..0....0..0..0....0..2..1....0..1..2....1..1..0

%e ..2..2..0....2..1..1....0..1..2....1..2..1....0..2..1....1..2..2....2..2..0

%e ..2..2..1....2..2..1....0..2..2....1..2..1....1..2..2....1..2..2....2..2..1

%e ..2..2..2....2..2..2....1..2..2....2..2..2....1..2..2....2..2..2....2..2..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 01 2013

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Last modified January 19 18:52 EST 2022. Contains 350466 sequences. (Running on oeis4.)