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A155353 Number of ways to place zero or more nonadjacent 2,1 2,2 3,0 3,1 3,3 4,2 4,3 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 7, 19, 37, 82, 439, 3646, 20995, 111047, 888450, 11127243, 160502934, 2195406729, 35231318268, 762257930909, 21186573131078, 666712624377399 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

COMMENTS

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

LINKS

Table of n, a(n) for n=4..20.

EXAMPLE

Maximal 12 X 12 X 12 example

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

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

............1.0.1

...........0.1.1.0

..........0.1.0.0.0

.........0.0.0.0.1.1

........0.1.1.0.1.0.1

.......0.1.0.1.0.1.1.0

......0.0.1.1.0.1.0.0.0

.....1.1.0.0.1.0.0.1.1.0

....1.0.1.1.0.0.0.1.0.1.1

...0.1.1.0.0.0.0.0.1.1.0.0

CROSSREFS

Sequence in context: A155342 A155408 A155358 * A155317 A237052 A155381

Adjacent sequences:  A155350 A155351 A155352 * A155354 A155355 A155356

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified August 20 06:41 EDT 2019. Contains 326139 sequences. (Running on oeis4.)