A155437 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 2,2 3,1 3,2 4,1 5,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 100, 428, 1830, 11336, 67788, 454698, 3575689, 35749465, 410313440, 5458200826, 83668909890

Offset

5,2

Links

Table of n, a(n) for n=5..19.

Example

Maximal 10 X 10 X 10 example
............0
...........1.1
..........1.0.1
.........0.1.1.0
........0.1.0.0.0
.......0.1.0.0.1.0
......0.0.0.0.0.1.0
.....1.1.0.0.0.0.1.1
....1.0.1.1.1.0.1.0.1
...0.1.1.0.0.0.0.1.1.0

Crossrefs

Sequence in context: A155329 A155424 A155349 * A155299 A155379 A155243

Adjacent sequences: A155434 A155435 A155436 * A155438 A155439 A155440

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved