A155248 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 2,1 3,0 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 209, 1577, 10287, 78555, 928301, 14022349, 239786776, 5085100887, 142197577695, 5014181558576, 216402828969373

Offset

3,2

Links

Table of n, a(n) for n=3..17.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........0.0.0
.........0.0.1.1
........1.1.0.1.1
.......1.1.0.0.1.1
......1.1.0.0.0.0.0
.....0.0.0.1.1.0.1.1
....1.1.1.0.1.1.0.1.1
...0.1.1.1.0.1.1.0.1.1

Crossrefs

Sequence in context: A155388 A155367 A155357 * A027452 A051937 A119327

Adjacent sequences: A155245 A155246 A155247 * A155249 A155250 A155251

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved