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A155380 Number of ways to place zero or more nonadjacent 1,0 1,1 2,1 3,1 3,2 4,2 5,2 5,3 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 4, 10, 19, 40, 120, 445, 2107, 10099, 50833, 296830, 2080084, 17252149, 164656985, 1767665953, 21481633518, 300312864497 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Table of n, a(n) for n=5..21.

EXAMPLE

Maximal 10 X 10 X 10 example

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

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

..........1.0.0

.........1.1.1.0

........0.0.1.1.1

.......1.1.0.0.1.0

......0.1.0.0.0.0.1

.....0.1.1.0.0.1.1.1

....0.0.1.0.1.1.1.0.0

...0.0.1.1.0.1.0.0.0.0

CROSSREFS

Sequence in context: A008118 A301160 A097116 * A155445 A133952 A155348

Adjacent sequences:  A155377 A155378 A155379 * A155381 A155382 A155383

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified January 28 06:29 EST 2020. Contains 331317 sequences. (Running on oeis4.)