A155411 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,1 3,2 4,1 5,2 5,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 37, 76, 258, 1393, 9223, 50174, 277825, 1912295, 17811734, 207588822, 2624271308, 35563828726, 553613643453

Offset

5,2

Links

Table of n, a(n) for n=5..20.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.1.0
.........1.0.1.1
........0.0.1.0.1
.......1.1.0.0.1.0
......1.0.0.0.0.0.1
.....0.1.1.0.0.1.0.1
....0.1.0.0.1.0.1.1.0
...0.0.1.1.0.1.1.0.0.0

Crossrefs

Sequence in context: A155378 A155438 A155396 * A155436 A155440 A155327

Adjacent sequences: A155408 A155409 A155410 * A155412 A155413 A155414

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved