A155267 - OEIS

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A155267

Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,1 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 79, 475, 4903, 39377, 335194, 4601560, 86035793, 1817145359, 47456653666, 1611117096227, 70329597516837

(list; graph; refs; listen; history; text; internal format)

OFFSET

4,2

LINKS

Table of n, a(n) for n=4..17.

EXAMPLE

Maximal 13 X 13 X 13 example

...............1

..............1.1

.............0.1.0

............0.1.0.0

...........1.0.1.0.0

..........1.1.0.0.1.1

.........0.1.0.0.1.1.0

........0.1.0.1.1.0.0.0

.......0.0.1.0.0.0.1.0.1

......0.0.0.0.0.0.1.1.0.1

.....0.1.1.0.1.1.0.1.0.1.0

....1.1.0.0.1.1.0.1.0.1.1.0

...1.1.0.1.1.0.0.0.1.0.1.0.0

CROSSREFS

Sequence in context: A163675 A152610 A155264 * A157837 A039367 A139697

Adjacent sequences: A155264 A155265 A155266 * A155268 A155269 A155270

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved