A155367 Number of ways to place zero or more nonadjacent (0,0) (1,0) (1,1) (2,0) (3,1) (4,0) (4,1) (5,1) polyhexes in any orientation on a planar n X n X n triangular grid.

1, 7, 19, 37, 209, 927, 3227, 19783, 150961, 985335, 8837609, 101553731, 1116357221, 14988545712

Offset

5,2

Comments

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

Links

Table of n, a(n) for n=5..18.

Example

Maximal 9 X 9 X 9 example:
...........0
..........1.1
.........0.1.0
........1.1.0.1
.......1.0.0.1.1
......1.1.0.0.0.1
.....0.0.0.0.0.1.0
....1.0.1.1.1.0.1.1
...1.1.1.0.1.0.0.1.0

Crossrefs

Sequence in context: A155364 A155332 A155388 * A155357 A155248 A027452

Adjacent sequences: A155364 A155365 A155366 * A155368 A155369 A155370

Keyword

nonn

Author

R. H. Hardin, Jan 22 2009

Status

approved