A155279 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 4,0 5,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 28, 131, 610, 2469, 15728, 124639, 969461, 10411634, 132835888, 1807916253

Offset

4,2

Links

Table of n, a(n) for n=4..16.

Example

Maximal 11 X 11 X 11 example
.............0
............1.1
...........0.0.1
..........1.0.0.1
.........1.0.0.0.1
........0.1.0.0.1.0
.......1.0.1.0.0.0.1
......0.1.0.1.1.0.1.0
.....0.1.0.0.0.0.0.1.0
....0.1.0.1.1.1.1.0.1.0
...1.1.0.1.0.0.0.1.0.1.1

Crossrefs

Sequence in context: A155224 A155238 A155320 * A155331 A155387 A155366

Adjacent sequences: A155276 A155277 A155278 * A155280 A155281 A155282

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved