A155264 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,1 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 13, 37, 79, 343, 3883, 32621, 226143, 2442908, 45791330, 912526379, 19385105798, 531941059542

Offset

4,2

Comments

Same series for 0,0 1,0 2,0 2,1 3,2 4,2 polyhexes.

Links

Table of n, a(n) for n=4..16.

Example

Maximal 11 X 11 X 11 example
.............1
............1.1
...........0.0.1
..........1.0.1.0
.........1.0.1.0.0
........1.0.0.0.0.0
.......0.1.1.0.1.1.1
......0.0.1.0.1.0.1.0
.....1.1.0.0.1.0.0.0.1
....0.1.0.0.0.0.1.0.1.0
...0.0.1.1.1.0.1.1.1.0.0

Crossrefs

Sequence in context: A089114 A163675 A152610 * A155267 A157837 A039367

Adjacent sequences: A155261 A155262 A155263 * A155265 A155266 A155267

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved