A155370 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,1 3,1 4,1 4,2 5,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 124, 545, 2932, 15809, 100710, 785638, 7143835, 76372256, 962177079, 14293799953, 248275319618

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
.........0.1.1.0
........0.0.0.1.1
.......0.0.0.0.1.1
......0.1.1.0.0.0.0
.....0.1.1.0.1.1.0.0
....1.1.0.0.0.1.1.1.1
...1.1.0.0.0.0.0.0.1.1

Crossrefs

Sequence in context: A098481 A155334 A155422 * A155442 A155324 A155325

Adjacent sequences: A155367 A155368 A155369 * A155371 A155372 A155373

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved