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A155323
Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 2,2 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.
0
1, 7, 19, 37, 61, 547, 3879, 20553, 82301, 862099, 11383399, 147116137, 1584915709, 26192809787, 600459150255, 15941874201057
OFFSET
4,2
COMMENTS
Same series for 0,0 1,0 2,0 2,1 2,2 3,2 4,2 polyhexes.
EXAMPLE
Maximal 9 X 9 X 9 example
...........1
..........0.1
.........1.1.1
........0.0.1.0
.......0.0.1.0.0
......0.0.0.0.0.0
.....1.0.1.0.1.1.1
....0.1.1.0.1.1.0.0
...1.1.1.0.1.0.1.0.0
CROSSREFS
Sequence in context: A155352 A155361 A155315 * A121091 A213489 A288021
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved