A155442 Number of ways to place zero or more nonadjacent 1,0 2,0 2,2 3,1 3,2 4,1 5,1 6,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 124, 550, 2077, 9417, 59328, 393791, 2721517, 23341616, 236771490, 2617082602

Offset

6,2

Links

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

Example

Maximal 11 X 11 X 11 example
.............0
............1.0
...........1.0.1
..........0.1.1.0
.........0.1.0.0.0
........0.1.0.0.1.0
.......0.1.0.0.0.1.0
......0.0.0.0.0.0.1.0
.....1.1.0.0.0.0.0.1.1
....0.0.1.1.1.1.0.1.0.1
...0.1.1.0.0.0.0.0.1.0.0

Crossrefs

Sequence in context: A155334 A155422 A155370 * A155324 A155325 A155255

Adjacent sequences: A155439 A155440 A155441 * A155443 A155444 A155445

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved