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A155304
Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,1 3,2 4,3 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 13, 37, 73, 309, 2413, 28415, 205131, 1898471, 29029014, 631146446, 14579044094, 368315888227, 12424744049760, 572778669577292
OFFSET
4,2
EXAMPLE
Maximal 11 X 11 X 11 example
.............0
............1.1
...........1.0.1
..........0.0.1.0
.........0.1.0.1.0
........1.1.0.0.0.1
.......1.0.0.1.1.0.1
......0.1.1.0.0.1.1.0
.....1.0.0.0.0.0.0.0.1
....1.0.1.1.0.0.1.1.0.1
...0.1.1.0.0.0.0.0.1.1.0
CROSSREFS
Sequence in context: A155262 A155301 A155284 * A183454 A155265 A155253
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved