A155356 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 2,1 2,2 3,1 3,2 polyhexes in any orientation on a planar n X n X n triangular grid.

1, 4, 13, 28, 49, 268, 2207, 13527, 65442, 532199, 7461240, 113949026, 1537124321, 25756946558, 635120397887, 20097790938202, 675874617024695, 25863870998834477, 1279264911762340761

Offset

3,2

Comments

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

Links

Table of n, a(n) for n=3..21.

Example

Maximal 10 X 10 X 10 example
............0
...........1.1
..........1.1.1
.........0.1.1.1
........0.0.0.0.0
.......0.0.1.1.0.0
......0.0.1.1.1.0.0
.....1.1.0.1.1.0.1.1
....1.1.1.0.1.0.1.1.1
...1.1.1.0.0.0.1.1.1.0

Crossrefs

Sequence in context: A155435 A155371 A155355 * A060488 A054968 A087035

Adjacent sequences: A155353 A155354 A155355 * A155357 A155358 A155359

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved