A155408 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 2,2 3,1 3,2 4,3 5,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 82, 389, 2228, 11375, 55979, 368808, 3167853, 30342483, 321262692, 3912167616, 56990411793

Offset

5,2

Links

Table of n, a(n) for n=5..19.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.1.0
.........0.0.1.1
........0.0.1.1.0
.......0.0.0.0.1.1
......0.1.1.0.0.0.0
.....1.1.0.0.0.1.0.1
....0.1.1.0.1.1.1.1.0
...1.1.0.0.1.0.1.0.0.0

Crossrefs

Sequence in context: A155363 A155395 A155342 * A155358 A155353 A155317

Adjacent sequences: A155405 A155406 A155407 * A155409 A155410 A155411

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved