A155299 - OEIS

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A155299

Number of ways to place zero or more nonadjacent 1,1 2,1 3,0 3,1 4,2 5,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 100, 478, 3236, 19635, 120080, 957011, 10308520, 134839273, 1943304769, 32282816021, 657583832803, 16484816876989

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

OFFSET

5,2

LINKS

Table of n, a(n) for n=5..20.

EXAMPLE

Maximal 12 X 12 X 12 example

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

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

............0.0.0

...........0.0.0.0

..........0.1.0.1.0

.........0.1.0.0.1.0

........1.1.0.0.0.1.1

.......0.0.1.0.0.1.0.0

......1.0.0.1.0.1.0.0.1

.....0.1.0.0.0.0.0.0.1.0

....0.0.1.1.1.0.1.1.1.0.0

...0.0.1.0.0.0.0.0.0.1.0.0

CROSSREFS

Sequence in context: A155424 A155349 A155437 * A155379 A155243 A155417

Adjacent sequences: A155296 A155297 A155298 * A155300 A155301 A155302

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved