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A155405 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 3,3 4,1 4,2 5,3 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 7, 19, 37, 61, 179, 1570, 9884, 43279, 162911, 1062503, 13577598, 173995382, 1740580398, 16367827293, 223104829665, 4754997792283, 115851743032210 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Table of n, a(n) for n=5..22.

EXAMPLE

Maximal 10 X 10 X 10 example

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

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

..........1.1.0

.........0.0.1.1

........0.1.1.0.0

.......0.0.0.1.0.0

......1.0.1.0.0.1.0

.....0.1.1.0.1.1.0.1

....1.1.0.1.0.0.1.1.0

...0.0.1.0.0.0.1.0.1.0

CROSSREFS

Sequence in context: A002407 A098484 A155443 * A155448 A155446 A155372

Adjacent sequences:  A155402 A155403 A155404 * A155406 A155407 A155408

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified December 3 19:39 EST 2021. Contains 349468 sequences. (Running on oeis4.)