A155241 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 181, 1229, 8379, 80551, 1100805, 17145265, 351104244, 9283888557, 306284314214

Offset

4,2

Links

Table of n, a(n) for n=4..15.

Example

Maximal 11 X 11 X 11 example
.............0
............1.0
...........0.1.1
..........1.0.0.1
.........0.1.1.0.1
........0.0.0.1.0.0
.......1.0.1.0.1.0.0
......1.0.1.0.0.0.1.1
.....1.0.1.0.1.1.1.0.0
....0.1.0.1.0.0.0.0.1.1
...0.1.0.1.0.0.1.1.1.0.0

Crossrefs

Sequence in context: A371512 A298683 A173872 * A155222 A155283 A155282

Adjacent sequences: A155238 A155239 A155240 * A155242 A155243 A155244

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved