A155262 Number of ways to place zero or more nonadjacent 1,1 2,1 2,2 3,0 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 73, 270, 3023, 31666, 204526, 1765714, 30617532, 748500437, 15766186082, 363909913887, 12760152079877, 642694450893529

Offset

4,2

Comments

Same series for 1,0 2,0 2,1 2,2 3,0 4,1 polyhexes.

Links

Table of n, a(n) for n=4..18.

Example

Maximal 11 X 11 X 11 example
.............0
............1.0
...........0.1.1
..........1.1.0.0
.........0.1.0.1.1
........0.0.0.0.1.0
.......0.1.0.1.0.1.1
......0.1.1.1.0.1.0.0
.....1.0.0.0.1.0.0.0.1
....0.1.1.1.0.0.1.1.1.0
...0.1.0.1.0.0.0.1.0.1.0

Crossrefs

Sequence in context: A003154 A083577 A155285 * A155301 A155284 A155304

Adjacent sequences: A155259 A155260 A155261 * A155263 A155264 A155265

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved