A155256 Number of ways to place zero or more nonadjacent 1,1 2,1 2,2 3,1 4,0 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 55, 244, 1426, 10764, 97667, 1037959, 13184770, 219939446, 4610420436, 119066459836

Offset

4,2

Links

Table of n, a(n) for n=4..16.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.0.0
.........1.1.1.1
........0.0.0.0.1
.......1.0.1.1.0.0
......0.1.0.1.0.1.0
.....0.1.0.1.0.1.1.0
....0.1.0.1.0.0.0.1.0
...0.1.1.0.1.0.0.0.1.1

Crossrefs

Sequence in context: A155292 A155276 A155270 * A155230 A155231 A155261

Adjacent sequences: A155253 A155254 A155255 * A155257 A155258 A155259

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved