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A155269 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,1 3,2 4,1 polyhexes in any orientation on a planar nXnXn triangular grid. 0
1, 4, 10, 19, 46, 196, 1032, 4951, 26637, 188993, 1709202, 17529087, 202068348, 2791380782, 47026449297, 942262652574, 22038920608740, 607442111573650 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..21.

EXAMPLE

Maximal 9 X 9 X 9 example

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

..........1.0

.........0.1.1

........0.1.1.0

.......0.0.0.1.0

......1.0.0.0.0.0

.....0.1.1.0.0.1.0

....0.1.1.0.1.1.1.1

...0.0.0.1.0.0.1.0.0

CROSSREFS

Sequence in context: A155445 A133952 A155348 * A155322 A251176 A155428

Adjacent sequences:  A155266 A155267 A155268 * A155270 A155271 A155272

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved

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Last modified January 18 01:05 EST 2020. Contains 330995 sequences. (Running on oeis4.)