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A155238
Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 4,1 polyhexes in any orientation on a planar n X n X n triangular grid.
0
1, 4, 13, 28, 125, 568, 3422, 27373, 226848, 2490002, 34395449, 564841115, 11835714950, 297683710781, 9228089921657
OFFSET
3,2
EXAMPLE
Maximal 9 X 9 X 9 example
...........0
..........0.0
.........1.1.1
........1.0.0.1
.......0.0.0.0.0
......1.1.0.0.1.1
.....1.0.0.0.0.0.1
....1.0.1.0.0.1.0.1
...0.1.0.1.1.1.0.1.0
CROSSREFS
Sequence in context: A155326 A155257 A155224 * A155320 A155279 A155331
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 22 2009
STATUS
approved