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A155394
Number of ways to place zero or more nonadjacent 1,1 2,1 3,0 3,1 4,2 4,3 5,2 6,2 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 7, 19, 37, 67, 219, 1086, 6381, 31966, 154641, 952314, 7600004, 73667522, 781898311, 8779500403
OFFSET
6,2
EXAMPLE
Maximal 11 X 11 X 11 example
.............0
............1.0
...........0.1.0
..........0.0.1.1
.........0.1.1.0.0
........0.0.0.1.0.0
.......0.0.1.0.1.0.0
......1.0.1.0.0.0.1.0
.....0.1.1.0.1.1.1.0.0
....0.1.0.1.0.0.0.1.1.1
...0.1.0.0.0.0.0.1.0.0.0
CROSSREFS
Sequence in context: A121091 A213489 A288021 * A155412 A155420 A155434
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved