A155218 - OEIS

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A155218

Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 64, 604, 5668, 60291, 1139786, 28911749, 917529031, 42684328880, 2779416860900, 242990212063594, 29572386974464964, 5010503933132486018, 1166195763716912084751, 374917567112932723176757

(list; graph; refs; listen; history; text; internal format)

OFFSET

2,2

LINKS

Table of n, a(n) for n=2..18.

EXAMPLE

Maximal 13 X 13 X 13 example

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

..............1.1

.............1.0.0

............0.0.1.1

...........1.1.0.0.1

..........1.0.0.1.0.0

.........0.0.1.1.0.1.1

........1.0.0.0.0.1.0.0

.......1.0.1.0.1.0.0.1.1

......0.1.0.1.0.1.1.0.0.1

.....1.0.0.1.0.0.0.0.1.0.0

....1.0.1.0.0.1.1.0.1.0.1.0

...0.1.0.1.1.0.0.1.0.1.0.1.1

CROSSREFS

Sequence in context: A155401 A346851 A155384 * A305483 A046137 A193643

Adjacent sequences: A155215 A155216 A155217 * A155219 A155220 A155221

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 22 2009

STATUS

approved