A155326 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 3,1 4,0 5,1 polyhexes in any orientation on a planar n X n X n triangular grid.

1, 4, 13, 28, 111, 502, 1855, 10932, 85106, 591988, 5415550, 64685900, 769802654, 11442223576

Offset

4,2

Comments

Same series for 1,0 1,1 2,0 2,1 3,0 4,0 4,1 5,1 polyhexes.

Links

Table of n, a(n) for n=4..17.

Example

Maximal 8 X 8 X 8 example
..........1
.........0.1
........1.1.0
.......0.1.0.1
......1.1.0.1.0
.....0.0.0.0.1.1
....1.1.1.1.0.1.0
...1.0.1.0.1.0.1.1

Crossrefs

Sequence in context: A009561 A155266 A155413 * A155257 A155224 A155238

Adjacent sequences: A155323 A155324 A155325 * A155327 A155328 A155329

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved