A155233 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,0 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 82, 574, 3503, 36335, 487910, 7124817, 157571588, 4154930503, 146494880857, 6891864295735

Offset

3,2

Links

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

Example

Maximal 11 X 11 X 11 example
.............1
............1.1
...........0.0.1
..........0.1.0.1
.........1.0.1.0.0
........1.1.0.1.1.0
.......1.0.0.0.1.0.1
......1.0.1.0.0.0.1.1
.....0.0.1.1.1.1.0.0.1
....1.0.0.0.0.0.0.1.0.1
...1.1.1.1.0.1.1.1.1.0.0

Crossrefs

Sequence in context: A058481 A220387 A155294 * A183914 A279216 A245769

Adjacent sequences: A155230 A155231 A155232 * A155234 A155235 A155236

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved