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A155369 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,1 3,1 3,2 4,1 4,3 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 4, 10, 22, 40, 103, 496, 3099, 16980, 88897, 547244, 4508233, 48937458, 595010305, 7745612856, 114311761273 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..19.

EXAMPLE

Maximal 11 X 11 X 11 example

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

............0.1

...........0.1.0

..........1.1.1.1

.........1.1.0.0.0

........0.0.0.0.1.1

.......0.0.1.1.1.1.0

......1.0.0.0.1.0.0.1

.....0.1.0.0.1.0.0.1.0

....1.1.1.1.0.0.1.1.1.1

...0.0.0.1.1.0.1.1.0.0.0

CROSSREFS

Sequence in context: A177736 A061777 A298030 * A155404 A155360 A155382

Adjacent sequences:  A155366 A155367 A155368 * A155370 A155371 A155372

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified September 25 07:27 EDT 2021. Contains 347654 sequences. (Running on oeis4.)