A155347 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 3,1 4,2 5,2 6,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 52, 178, 691, 3685, 20423, 128624, 1025960, 9573074, 102844369

Offset

6,2

Links

Table of n, a(n) for n=6..17.

Example

Maximal 12 X 12 X 12 example
..............0
.............0.0
............0.0.0
...........1.1.0.0
..........0.0.1.1.0
.........0.0.0.0.1.1
........0.0.1.1.0.0.1
.......0.1.1.0.0.1.0.0
......1.1.0.0.1.1.0.0.1
.....1.0.0.1.1.0.0.1.1.0
....0.0.1.1.0.0.1.1.0.0.0
...0.0.0.0.0.1.1.0.0.0.0.0

Crossrefs

Sequence in context: A332364 A100450 A155423 * A155385 A155345 A155309

Adjacent sequences: A155344 A155345 A155346 * A155348 A155349 A155350

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved