A155338 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,1 4,2 5,2 6,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 64, 199, 919, 4123, 24600, 145752, 1212971, 10549470, 114622513

Offset

6,2

Links

Table of n, a(n) for n=6..17.

Example

Maximal 11 X 11 X 11 example
.............0
............0.0
...........1.0.0
..........0.1.0.0
.........0.0.1.1.1
........0.0.0.0.0.1
.......0.0.1.0.0.0.1
......0.0.1.0.0.0.0.0
.....1.1.1.0.0.0.1.1.1
....1.0.0.0.0.0.1.0.0.0
...1.0.0.0.1.1.1.0.0.0.0

Crossrefs

Sequence in context: A165683 A092359 A259797 * A155401 A346851 A155384

Adjacent sequences: A155335 A155336 A155337 * A155339 A155340 A155341

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved