A155377 Number of ways to place zero or more nonadjacent 1,1 2,1 3,1 3,2 4,0 4,1 5,1 6,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 153, 637, 2331, 11267, 74210, 497308, 3765392, 35883138, 379301928, 4460755344

Offset

6,2

Links

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

Example

Maximal 10 X 10 X 10 example
............0
...........1.0
..........0.1.1
.........0.0.1.0
........0.1.0.1.0
.......0.1.0.1.1.0
......0.1.1.0.0.1.0
.....1.1.0.0.1.0.0.0
....0.1.0.1.1.1.1.1.1
...0.1.0.0.0.0.0.1.0.0

Crossrefs

Sequence in context: A155239 A217421 A155376 * A155227 A155319 A155318

Adjacent sequences: A155374 A155375 A155376 * A155378 A155379 A155380

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved