A155349 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,1 4,2 5,1 5,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 100, 428, 1794, 11180, 68280, 460602, 3595480, 35769940, 408682401, 5473453986, 84561686844

Offset

5,2

Links

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

Example

Maximal 10 X 10 X 10 example
............0
...........1.0
..........1.0.0
.........0.1.1.1
........0.0.0.0.1
.......0.1.0.0.1.0
......0.0.1.0.0.0.0
.....1.1.1.0.0.0.1.1
....1.0.0.0.1.0.1.0.1
...0.1.0.0.0.1.1.0.0.0

Crossrefs

Sequence in context: A155431 A155329 A155424 * A155437 A155299 A155379

Adjacent sequences: A155346 A155347 A155348 * A155350 A155351 A155352

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved