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A155318 Number of ways to place zero or more nonadjacent 1,0 1,1 2,1 2,2 3,1 4,1 5,1 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 7, 19, 37, 162, 682, 2862, 19723, 141397, 1047499, 10569960, 123328797, 1599865270, 26321921029 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Table of n, a(n) for n=5..18.

EXAMPLE

Maximal 9 X 9 X 9 example

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

..........1.1

.........0.1.1

........0.1.0.0

.......0.1.0.1.0

......0.1.0.0.1.0

.....1.0.0.0.0.1.0

....1.1.1.1.1.0.1.1

...0.1.0.0.0.0.1.1.0

CROSSREFS

Sequence in context: A155377 A155227 A155319 * A155280 A155365 A155364

Adjacent sequences:  A155315 A155316 A155317 * A155319 A155320 A155321

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified January 22 21:47 EST 2022. Contains 350504 sequences. (Running on oeis4.)