A155348 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 4,3 4,4 5,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 19, 43, 128, 488, 2206, 10000, 48377, 276446, 1912377, 15358537, 137081258, 1363205310, 15492211198, 203922791257, 3090086318993

Offset

5,2

Links

Table of n, a(n) for n=5..22.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.0.0
.........0.1.1.0
........0.1.0.0.1
.......1.1.0.1.1.0
......0.0.1.0.0.1.0
.....0.1.0.0.1.0.1.1
....0.0.1.1.1.0.1.0.0
...0.0.1.0.0.1.0.0.0.0

Crossrefs

Sequence in context: A155380 A155445 A133952 * A155269 A155322 A251176

Adjacent sequences: A155345 A155346 A155347 * A155349 A155350 A155351

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved