A155285 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 4,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 73, 258, 1871, 22758, 161452, 1241904, 16300245, 324762872, 7210518148, 157052254320, 4356147792581

Offset

4,2

Links

Table of n, a(n) for n=4..17.

Example

Maximal 11 X 11 X 11 example
.............0
............1.1
...........1.0.1
..........0.0.0.1
.........1.1.0.1.0
........1.0.0.0.0.1
.......1.0.0.1.0.0.1
......0.1.1.0.1.1.1.0
.....1.0.0.0.0.0.0.0.1
....1.0.0.1.0.0.1.0.0.1
...0.1.1.1.0.0.0.1.1.1.0

Crossrefs

Sequence in context: A158864 A003154 A083577 * A155262 A155301 A155284

Adjacent sequences: A155282 A155283 A155284 * A155286 A155287 A155288

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved