A155422 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,1 4,1 5,2 6,1 6,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 118, 502, 1873, 7452, 43554, 288884, 1929451, 15024812, 143416801, 1509097096

Offset

6,2

Links

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

Example

Maximal 11 X 11 X 11 example
.............0
............0.1
...........0.0.1
..........0.1.1.0
.........1.1.0.0.0
........1.0.0.0.1.1
.......0.1.0.0.0.0.1
......0.0.0.0.0.0.1.0
.....0.0.0.1.1.0.0.1.0
....1.0.1.1.0.1.0.1.0.0
...0.1.1.0.0.0.0.0.1.1.0

Crossrefs

Sequence in context: A155359 A098481 A155334 * A155370 A155442 A155324

Adjacent sequences: A155419 A155420 A155421 * A155423 A155424 A155425

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved