A155375 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 2,1 3,0 4,0 4,1 5,0 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 37, 146, 614, 2467, 11092, 69586, 500162, 4040869, 39876354, 445952771

Offset

5,2

Links

Table of n, a(n) for n=5..17.

Example

Maximal 9 X 9 X 9 example
...........1
..........0.1
.........0.1.1
........1.0.0.1
.......1.0.0.1.1
......1.1.0.0.0.1
.....1.0.0.0.0.0.0
....1.1.0.0.1.0.1.0
...1.0.0.1.1.1.1.1.1

Crossrefs

Sequence in context: A067633 A297391 A108489 * A155307 A155344 A155418

Adjacent sequences: A155372 A155373 A155374 * A155376 A155377 A155378

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved