A155374 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,0 3,1 4,1 5,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 52, 254, 1061, 4586, 28708, 218507, 1736540, 17357415, 205447067, 2686619638

Offset

5,2

Links

Table of n, a(n) for n=5..17.

Example

Maximal 9 X 9 X 9 example
...........0
..........0.1
.........1.1.0
........1.1.0.1
.......1.1.0.0.1
......1.0.0.0.1.1
.....0.0.0.0.0.1.1
....1.1.1.1.0.0.1.0
...0.0.1.1.1.1.0.1.0

Crossrefs

Sequence in context: A155419 A155246 A155414 * A155272 A092053 A072630

Adjacent sequences: A155371 A155372 A155373 * A155375 A155376 A155377

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved