A155261 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 2,1 3,0 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 55, 353, 2143, 18201, 203783, 2290841, 37082423, 818768313, 20744782567, 698778878809, 29337409298279

Offset

3,2

Links

Table of n, a(n) for n=3..16.

Example

Maximal 10 X 10 X 10 example
............1
...........1.1
..........0.1.0
.........1.1.0.0
........0.0.0.0.0
.......0.1.1.0.1.0
......1.0.1.1.1.0.1
.....0.1.0.0.0.0.1.0
....1.1.0.1.1.1.0.1.1
...1.1.0.1.0.1.1.0.1.1

Crossrefs

Sequence in context: A155256 A155230 A155231 * A365444 A268239 A350222

Adjacent sequences: A155258 A155259 A155260 * A155262 A155263 A155264

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved