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A224020 Number of nX4 0..3 arrays with rows nondecreasing and antidiagonals unimodal 1
35, 1225, 32523, 772683, 17735200, 403836633, 9186127249, 208983591829, 4754911670136, 108190494364824, 2461721043138176, 56012981686098087, 1274495739407259502, 28999333370466443973, 659838457829407289280 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A224024

LINKS

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

FORMULA

Empirical: a(n) = 35*a(n-1) -347*a(n-2) +1689*a(n-3) -2986*a(n-4) -2311*a(n-5) +23532*a(n-6) -23864*a(n-7) -36468*a(n-8) +100464*a(n-9) +94080*a(n-10)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A095153 A223989 A224387 * A009979 A238379 A158733

Adjacent sequences:  A224017 A224018 A224019 * A224021 A224022 A224023

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 30 2013

STATUS

approved

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Last modified December 10 15:09 EST 2019. Contains 329896 sequences. (Running on oeis4.)