A155320 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,0 4,0 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 28, 129, 586, 2176, 14358, 112046, 791851, 8217946, 101868365, 1252862099, 20806137393

Offset

4,2

Links

Table of n, a(n) for n=4..17.

Example

Maximal 11 X 11 X 11 example
.............1
............1.1
...........1.0.0
..........1.0.0.1
.........1.1.0.1.1
........0.0.0.0.0.1
.......0.0.0.0.0.0.1
......1.1.1.1.1.0.1.1
.....0.1.0.0.1.0.0.0.0
....1.0.0.1.0.0.1.0.0.1
...1.1.1.1.1.0.1.1.1.1.1

Crossrefs

Sequence in context: A155257 A155224 A155238 * A155279 A155331 A155387

Adjacent sequences: A155317 A155318 A155319 * A155321 A155322 A155323

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved