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A155307
Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 3,0 3,1 4,0 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 4, 13, 37, 146, 620, 2737, 17298, 136979, 1185666, 12752003, 161758550, 2364549128, 42702118766
OFFSET
4,2
COMMENTS
Same series for 0,0 1,0 2,0 2,1 3,0 3,1 4,0 polyhexes.
EXAMPLE
Maximal 11 X 11 X 11 example
.............1
............0.1
...........0.1.0
..........1.0.1.1
.........1.0.0.0.1
........0.1.0.0.0.0
.......1.1.0.0.1.1.0
......1.0.0.1.1.0.1.1
.....0.0.0.0.0.0.0.0.0
....1.1.0.1.1.0.0.1.1.0
...0.0.1.1.0.0.1.1.0.1.1
CROSSREFS
Sequence in context: A297391 A108489 A155375 * A155344 A155418 A155235
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved