A155418 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 3,1 4,1 5,0 5,1 6,0 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 37, 146, 650, 2757, 12196, 62521, 379032, 2723899, 22610728

Offset

6,2

Links

Table of n, a(n) for n=6..17.

Example

Maximal 10 X 10 X 10 example
............1
...........0.1
..........0.1.0
.........1.0.1.0
........1.0.0.1.0
.......0.1.0.0.1.1
......0.1.0.0.0.0.1
.....0.1.0.0.0.0.0.0
....1.1.0.0.1.1.1.1.0
...1.0.0.1.1.0.0.0.1.1

Crossrefs

Sequence in context: A155375 A155307 A155344 * A155235 A024450 A047094

Adjacent sequences: A155415 A155416 A155417 * A155419 A155420 A155421

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved