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A224006 Number of n X n 0..2 arrays with rows nondecreasing and antidiagonals unimodal 0
3, 36, 868, 28541, 1108969, 47735665, 2200064042, 106468976628, 5346274348879, 276427362685199, 14638913051219770, 790954334539356094, 43473056647367595435, 2424900281957535784114, 137007153893707984264455 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A224012

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A224347 A227251 A326273 * A004824 A132912 A303866

Adjacent sequences:  A224003 A224004 A224005 * A224007 A224008 A224009

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 30 2013

STATUS

approved

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Last modified December 9 06:07 EST 2021. Contains 349627 sequences. (Running on oeis4.)