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A269138 Number of nX3 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once. 1
60, 1164, 18556, 275796, 3924212, 54199284, 732561916, 9740150372, 127846717716, 1660741102212, 21389485726684, 273519303765844, 3476418550368820, 43954347343683220, 553215363420258236, 6935081471870462788 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A269143.

LINKS

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

FORMULA

Empirical: a(n) = 26*a(n-1) -199*a(n-2) +408*a(n-3) -463*a(n-4) +322*a(n-5) -141*a(n-6) +36*a(n-7) -4*a(n-8) for n>9

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A269143.

Sequence in context: A056346 A283722 A105252 * A146347 A289156 A288960

Adjacent sequences:  A269135 A269136 A269137 * A269139 A269140 A269141

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 20 2016

STATUS

approved

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Last modified June 23 07:14 EDT 2021. Contains 345395 sequences. (Running on oeis4.)