A155302 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,2 3,3 4,2 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 19, 31, 129, 761, 3423, 12503, 65847, 587331, 5621100, 47590431, 445495212, 5880381069, 98943434625, 1748899641272, 32546795958370, 732964964303388

Offset

4,2

Comments

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

Links

Table of n, a(n) for n=4..22.

Example

Maximal 13 X 13 X 13 example
...............0
..............0.0
.............1.0.1
............0.1.1.0
...........0.1.0.1.0
..........1.0.0.0.0.0
.........0.1.1.0.1.0.1
........1.1.0.0.0.1.1.0
.......0.0.1.0.0.1.0.1.0
......1.0.0.0.0.0.0.0.0.0
.....0.1.1.0.1.0.1.0.1.0.1
....1.1.0.0.0.1.1.0.0.1.1.0
...0.0.1.0.0.1.0.1.0.1.0.1.0

Crossrefs

Sequence in context: A098576 A063773 A155432 * A155362 A034966 A301256

Adjacent sequences: A155299 A155300 A155301 * A155303 A155304 A155305

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved