A155339 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 2,2 3,0 3,1 3,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 3, 7, 13, 23, 37, 183, 1053, 5351, 24397, 99215, 617661, 5897471, 64288141, 714391583, 7672307261, 95370104207, 1561595349917, 31946273565055

Offset

3,2

Links

Table of n, a(n) for n=3..21.

Example

Maximal 10 X 10 X 10 example
............1
...........1.0
..........0.1.1
.........1.1.0.1
........0.0.0.0.0
.......0.1.0.1.1.0
......1.0.1.1.0.0.1
.....0.1.0.0.1.0.1.0
....1.1.0.0.1.0.0.1.1
...1.0.1.1.0.0.1.1.0.1

Crossrefs

Sequence in context: A053599 A212146 A136851 * A122886 A154691 A306902

Adjacent sequences: A155336 A155337 A155338 * A155340 A155341 A155342

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved