A155232 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 2,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 22, 40, 361, 2821, 19057, 110575, 1423822, 26284909, 502358770, 9341556682, 253322462407, 10114422061267, 485429682957349, 25616146962812161, 1724462843271452173, 157410261704230494205

Offset

2,2

Links

Table of n, a(n) for n=2..20.

Example

Maximal 13 X 13 X 13 example
...............1
..............1.1
.............1.0.1
............0.0.0.0
...........1.0.1.1.1
..........1.0.0.0.1.0
.........1.1.1.0.1.0.1
........0.0.0.0.0.0.0.1
.......1.0.1.0.0.0.1.1.1
......0.1.1.0.0.0.0.0.0.0
.....1.0.1.0.1.0.1.0.1.0.1
....1.0.0.0.0.1.0.1.1.0.0.1
...1.1.1.0.1.1.1.0.1.0.1.1.1

Crossrefs

Sequence in context: A155287 A155337 A155402 * A188281 A227327 A023609

Adjacent sequences: A155229 A155230 A155231 * A155233 A155234 A155235

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved