A155335 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,1 5,2 6,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 58, 199, 688, 3581, 19670, 126183, 979162, 8439890, 86791208, 1020461563

Offset

6,2

Links

Table of n, a(n) for n=6..18.

Example

Maximal 12 X 12 X 12 example
..............1
.............0.1
............1.0.1
...........1.0.1.0
..........1.0.0.1.0
.........0.1.0.1.0.1
........0.1.0.1.0.0.1
.......0.0.1.0.0.0.0.1
......1.0.0.1.0.0.0.1.0
.....0.1.0.0.0.0.0.0.1.0
....0.0.1.1.0.0.0.0.1.0.0
...0.0.0.0.1.1.1.0.1.0.0.0

Crossrefs

Sequence in context: A069005 A000413 A263335 * A155226 A229442 A179406

Adjacent sequences: A155332 A155333 A155334 * A155336 A155337 A155338

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved