A155395 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 3,2 4,1 5,2 6,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 82, 304, 1597, 8409, 37756, 200483, 1450289, 12807392, 119527765, 1178177160

Offset

6,2

Links

Table of n, a(n) for n=6..19.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........0.0.0
.........0.0.0.0
........0.1.1.1.0
.......1.1.0.0.0.0
......1.0.1.0.0.0.1
.....1.0.0.0.1.0.1.0
....0.0.0.0.0.1.1.0.0
...0.0.0.1.1.1.0.0.0.0

Crossrefs

Sequence in context: A155440 A155327 A155363 * A155342 A155408 A155358

Adjacent sequences: A155392 A155393 A155394 * A155396 A155397 A155398

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved