A155234 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 73, 777, 9141, 72173, 857297, 18077297, 462703693, 12835269909, 499538698537, 27296320407513, 1893299363272421, 164544756777460349

Offset

3,2

Links

Table of n, a(n) for n=3..17.

Example

Maximal 7 X 7 X 7 example
.........0
........1.1
.......0.0.1
......0.0.1.1
.....1.1.0.0.0
....1.0.0.1.0.1
...1.1.0.0.1.1.1

Crossrefs

Sequence in context: A183454 A155265 A155253 * A222964 A296312 A089114

Adjacent sequences: A155231 A155232 A155233 * A155235 A155236 A155237

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved