A155275 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,2 3,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 43, 106, 578, 6127, 50784, 412459, 4183946, 65535514, 1436245357, 34233363901, 941805410568, 32559701412869

Offset

3,2

Links

Table of n, a(n) for n=3..17.

Example

Maximal 12 X 12 X 12 example
..............1
.............1.0
............1.1.0
...........0.0.1.1
..........1.0.0.0.0
.........0.1.0.1.1.0
........0.1.0.0.0.1.1
.......1.1.1.0.0.0.1.0
......0.0.0.0.1.0.1.0.1
.....1.0.0.0.1.0.0.0.1.0
....1.1.1.0.0.1.0.0.0.1.0
...1.0.0.1.0.1.1.1.0.1.1.1

Crossrefs

Sequence in context: A048488 A155303 A268801 * A155268 A124700 A155336

Adjacent sequences: A155272 A155273 A155274 * A155276 A155277 A155278

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved