A155266 - OEIS

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A155266

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

1, 4, 13, 28, 70, 418, 3187, 20380, 144781, 1561781, 23475489, 388651137, 7313541265, 177385458253, 5624711721417, 217536953984714

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

OFFSET

3,2

LINKS

Table of n, a(n) for n=3..18.

EXAMPLE

Maximal 11 X 11 X 11 example

.............0

............1.0

...........1.1.1

..........0.0.1.1

.........1.1.0.0.0

........0.1.0.1.1.0

.......0.1.1.0.1.1.1

......1.0.1.0.0.0.1.0

.....1.1.0.0.1.1.0.0.1

....0.1.0.1.1.1.0.1.1.1

...0.1.1.0.1.0.0.1.1.0.0

CROSSREFS

Sequence in context: A372484 A112560 A009561 * A155413 A155326 A155257

Adjacent sequences: A155263 A155264 A155265 * A155267 A155268 A155269

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved