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A155273
Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 7, 19, 46, 163, 1024, 6441, 43301, 373095, 4261954, 57065692, 918668240, 18051831843, 438138199809
OFFSET
4,2
EXAMPLE
Maximal 13 X 13 X 13 example
...............1
..............0.1
.............0.1.1
............1.0.1.0
...........1.0.1.0.1
..........1.1.0.0.0.1
.........0.1.0.0.0.1.1
........0.0.1.0.0.0.1.0
.......1.0.0.0.0.0.1.0.1
......1.0.0.1.1.1.0.0.0.1
.....1.1.0.1.1.0.0.1.0.1.1
....0.1.0.1.0.0.1.1.0.0.1.0
...0.0.1.0.0.1.1.1.0.0.1.0.0
CROSSREFS
Sequence in context: A212955 A372881 A155415 * A277613 A278403 A143128
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved