A155245 Number of ways to place zero or more nonadjacent 0,0 1,0 2,1 2,2 3,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 70, 416, 2481, 24212, 281815, 3600076, 66159319, 1542429625, 45797988541, 1765262317904

Offset

3,2

Comments

Same series for 0,0 1,0 1,1 2,0 2,1 3,0 polyhexes.

Links

Table of n, a(n) for n=3..15.

Example

Maximal 11 X 11 X 11 example
.............1
............1.0
...........0.1.1
..........0.0.0.1
.........1.0.0.0.0
........1.0.0.0.1.1
.......0.1.1.0.1.0.0
......1.0.0.1.0.1.0.1
.....1.0.0.0.0.1.0.0.1
....0.1.0.1.1.0.0.0.1.0
...1.1.0.1.0.1.1.0.0.1.1

Crossrefs

Sequence in context: A000970 A247620 A240156 * A155291 A155221 A213569

Adjacent sequences: A155242 A155243 A155244 * A155246 A155247 A155248

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved