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A155259 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,0 4,1 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 13, 37, 111, 999, 5261, 42873, 550367, 5937880, 97204725, 2096426420, 47838274736 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..15.

EXAMPLE

Maximal 10 X 10 X 10 example

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

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

..........0.0.1

.........1.0.0.1

........1.1.0.1.1

.......1.0.0.0.0.0

......1.0.1.1.0.1.1

.....0.1.0.0.1.0.1.0

....1.0.0.1.0.1.0.1.0

...1.1.1.1.0.1.1.0.1.1

CROSSREFS

Sequence in context: A155228 A126367 A139926 * A155308 A166101 A195543

Adjacent sequences:  A155256 A155257 A155258 * A155260 A155261 A155262

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified December 11 12:33 EST 2019. Contains 329916 sequences. (Running on oeis4.)