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A155325
Number of ways to place zero or more nonadjacent 1,1 2,1 3,0 3,1 3,2 4,1 5,1 polyhexes in any orientation on a planar n X n X n triangular grid.
0
1, 7, 19, 37, 133, 535, 2615, 17641, 119940, 924944, 8924108, 102805254, 1407633936, 22958195053, 437437783099
OFFSET
5,2
EXAMPLE
Maximal 10 X 10 X 10 example
............0
...........0.1
..........0.1.0
.........1.1.1.0
........0.1.0.0.0
.......0.1.0.0.1.0
......0.0.0.0.0.1.0
.....0.1.0.0.0.1.1.1
....1.1.1.1.1.0.0.1.0
...0.0.0.1.0.0.0.0.1.0
CROSSREFS
Sequence in context: A155370 A155442 A155324 * A155255 A155251 A155239
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved