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A155229
Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 2,2 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 4, 10, 19, 54, 346, 1831, 9221, 66079, 717157, 8272905, 104484553, 1712695513, 36940968544, 931841300560, 27497789520438, 1009266090959240, 46345568210962143
OFFSET
3,2
EXAMPLE
Maximal 11 X 11 X 11 example
.............0
............1.0
...........1.1.1
..........0.0.1.0
.........0.0.0.0.0
........1.1.0.0.0.1
.......0.1.0.0.1.1.1
......0.1.1.0.0.1.0.0
.....1.0.0.0.1.0.0.1.1
....1.1.1.0.1.1.1.0.1.0
...0.0.1.0.0.0.1.0.1.1.0
CROSSREFS
Sequence in context: A251176 A155428 A155383 * A155220 A300018 A268221
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved