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A155302 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 3,3 4,2 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 4, 10, 19, 31, 129, 761, 3423, 12503, 65847, 587331, 5621100, 47590431, 445495212, 5880381069, 98943434625, 1748899641272, 32546795958370, 732964964303388 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

COMMENTS

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

LINKS

Table of n, a(n) for n=4..22.

EXAMPLE

Maximal 13 X 13 X 13 example

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

..............0.0

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

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

...........0.1.0.1.0

..........1.0.0.0.0.0

.........0.1.1.0.1.0.1

........1.1.0.0.0.1.1.0

.......0.0.1.0.0.1.0.1.0

......1.0.0.0.0.0.0.0.0.0

.....0.1.1.0.1.0.1.0.1.0.1

....1.1.0.0.0.1.1.0.0.1.1.0

...0.0.1.0.0.1.0.1.0.1.0.1.0

CROSSREFS

Sequence in context: A098576 A063773 A155432 * A155362 A034966 A301256

Adjacent sequences:  A155299 A155300 A155301 * A155303 A155304 A155305

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified November 30 17:12 EST 2021. Contains 349424 sequences. (Running on oeis4.)