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A224021 Number of nX5 0..3 arrays with rows nondecreasing and antidiagonals unimodal 1
56, 3136, 122523, 4002738, 120352359, 3491241557, 99853876444, 2841637297963, 80738139650660, 2292943314015674, 65111906248932329, 1848921234461230235, 52501963543862778240, 1490846712885812140128, 42334133889896297673617 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A224024

LINKS

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

FORMULA

Empirical: a(n) = 56*a(n-1) -1098*a(n-2) +10776*a(n-3) -59038*a(n-4) +197135*a(n-5) -527776*a(n-6) +1780117*a(n-7) -5020078*a(n-8) +3603978*a(n-9) -19091082*a(n-10) +61460622*a(n-11) +49090018*a(n-12) +274177128*a(n-13) +105163104*a(n-14) +354022404*a(n-15) +28705280*a(n-16) +147891456*a(n-17) -1275168*a(n-18) +15980544*a(n-19)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A223868 A223990 A224388 * A042513 A264941 A216704

Adjacent sequences:  A224018 A224019 A224020 * A224022 A224023 A224024

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 30 2013

STATUS

approved

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Last modified December 2 22:46 EST 2021. Contains 349445 sequences. (Running on oeis4.)