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A155326
Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 3,1 4,0 5,1 polyhexes in any orientation on a planar n X n X n triangular grid.
0
1, 4, 13, 28, 111, 502, 1855, 10932, 85106, 591988, 5415550, 64685900, 769802654, 11442223576
OFFSET
4,2
COMMENTS
Same series for 1,0 1,1 2,0 2,1 3,0 4,0 4,1 5,1 polyhexes.
EXAMPLE
Maximal 8 X 8 X 8 example
..........1
.........0.1
........1.1.0
.......0.1.0.1
......1.1.0.1.0
.....0.0.0.0.1.1
....1.1.1.1.0.1.0
...1.0.1.0.1.0.1.1
CROSSREFS
Sequence in context: A009561 A155266 A155413 * A155257 A155224 A155238
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 22 2009
STATUS
approved