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A155262 Number of ways to place zero or more nonadjacent 1,1 2,1 2,2 3,0 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 13, 37, 73, 270, 3023, 31666, 204526, 1765714, 30617532, 748500437, 15766186082, 363909913887, 12760152079877, 642694450893529 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

COMMENTS

Same series for 1,0 2,0 2,1 2,2 3,0 4,1 polyhexes.

LINKS

Table of n, a(n) for n=4..18.

EXAMPLE

Maximal 11 X 11 X 11 example

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

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

...........0.1.1

..........1.1.0.0

.........0.1.0.1.1

........0.0.0.0.1.0

.......0.1.0.1.0.1.1

......0.1.1.1.0.1.0.0

.....1.0.0.0.1.0.0.0.1

....0.1.1.1.0.0.1.1.1.0

...0.1.0.1.0.0.0.1.0.1.0

CROSSREFS

Sequence in context: A003154 A083577 A155285 * A155301 A155284 A155304

Adjacent sequences:  A155259 A155260 A155261 * A155263 A155264 A155265

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified December 14 14:20 EST 2019. Contains 329979 sequences. (Running on oeis4.)