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A155428
Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 4,3 5,4 5,5 6,4 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 4, 10, 19, 51, 170, 491, 1673, 7735, 36917, 181725, 1063340, 7115095, 51066154, 415590144, 3918376915
OFFSET
6,2
EXAMPLE
Maximal 10 X 10 X 10 example
............0
...........0.1
..........1.1.0
.........0.0.1.0
........1.0.0.1.0
.......0.1.1.0.1.1
......0.1.0.0.1.0.0
.....0.1.0.1.0.0.0.1
....1.1.0.0.1.1.1.1.0
...0.0.1.0.1.0.0.0.1.0
CROSSREFS
Sequence in context: A155269 A155322 A251176 * A155383 A155229 A155220
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved