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A223956 Number of nX3 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing 1
20, 295, 3471, 41006, 485714, 5777663, 68892600, 822141033, 9813968785, 117159879996, 1398692077165, 16698106010927, 199348287106117, 2379894628461976, 28412070357384947, 339193873130519142 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A223961

LINKS

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

FORMULA

Empirical: a(n) = 20*a(n-1) -105*a(n-2) +51*a(n-3) +589*a(n-4) +1340*a(n-5) -8833*a(n-6) -2855*a(n-7) +30423*a(n-8) +57774*a(n-9) -140760*a(n-10) -176184*a(n-11) +106272*a(n-12) +544320*a(n-13)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A016259 A271029 A047795 * A132168 A069326 A001708

Adjacent sequences:  A223953 A223954 A223955 * A223957 A223958 A223959

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 29 2013

STATUS

approved

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Last modified December 7 15:24 EST 2021. Contains 349581 sequences. (Running on oeis4.)