A155269 Number of ways to place zero or more nonadjacent 1,1 2,0 2,1 3,1 3,2 4,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 19, 46, 196, 1032, 4951, 26637, 188993, 1709202, 17529087, 202068348, 2791380782, 47026449297, 942262652574, 22038920608740, 607442111573650

Offset

4,2

Links

Table of n, a(n) for n=4..21.

Example

Maximal 9 X 9 X 9 example
...........0
..........1.0
.........0.1.1
........0.1.1.0
.......0.0.0.1.0
......1.0.0.0.0.0
.....0.1.1.0.0.1.0
....0.1.1.0.1.1.1.1
...0.0.0.1.0.0.1.0.0

Crossrefs

Sequence in context: A155445 A133952 A155348 * A155322 A251176 A155428

Adjacent sequences: A155266 A155267 A155268 * A155270 A155271 A155272

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved