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A166197 Number of nXnXn triangular nonnegative integer arrays, symmetric under 120 degree rotation, with all sums of an element and its neighbors <= 2 2
1, 3, 1, 2, 6, 12, 26, 90, 200, 665, 3980, 10515, 52518, 433447, 1973317, 14252749, 166762668, 1065468116, 11148385916, 193707228525, 1758897674635, 26740845738267, 672553810724428, 9032785397690122, 199494539604910376 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

R. H. Hardin, Table of n, a(n) for n=0..27

EXAMPLE

All solutions for n=4

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

....0.0......0.0......0.0......0.0......0.0......0.0..

...0.2.0....0.0.0....0.1.0....0.0.0....0.0.0....0.1.0.

..0.0.0.0..1.0.0.1..1.0.0.1..0.0.0.0..2.0.0.2..0.0.0.0

CROSSREFS

Sequence in context: A201655 A049917 A308709 * A010279 A024743 A024963

Adjacent sequences: A166194 A166195 A166196 * A166198 A166199 A166200

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 09 2009

STATUS

approved

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Last modified February 3 23:01 EST 2023. Contains 360045 sequences. (Running on oeis4.)