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A155302
Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 3,3 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 4, 10, 19, 31, 129, 761, 3423, 12503, 65847, 587331, 5621100, 47590431, 445495212, 5880381069, 98943434625, 1748899641272, 32546795958370, 732964964303388
OFFSET
4,2
COMMENTS
Same series for 1,1 2,0 2,1 2,2 3,1 3,2 3,3 4,2 polyhexes.
EXAMPLE
Maximal 13 X 13 X 13 example
...............0
..............0.0
.............1.0.1
............0.1.1.0
...........0.1.0.1.0
..........1.0.0.0.0.0
.........0.1.1.0.1.0.1
........1.1.0.0.0.1.1.0
.......0.0.1.0.0.1.0.1.0
......1.0.0.0.0.0.0.0.0.0
.....0.1.1.0.1.0.1.0.1.0.1
....1.1.0.0.0.1.1.0.0.1.1.0
...0.0.1.0.0.1.0.1.0.1.0.1.0
CROSSREFS
Sequence in context: A098576 A063773 A155432 * A155362 A034966 A301256
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved