A155410 Number of ways to place zero or more nonadjacent 1,0 1,1 2,1 3,2 3,3 4,2 5,2 5,3 polyhexes in any orientation on a planar n X n X n triangular grid.

1, 7, 19, 37, 94, 297, 1458, 9766, 53099, 308101, 2235851, 20215398, 229099105, 2888943253, 39401146662, 624852187290

Offset

5,2

Comments

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

Links

Table of n, a(n) for n=5..20.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.1.0
.........0.1.0.0
........1.1.0.0.0
.......0.0.1.0.1.1
......1.0.1.1.0.1.0
.....1.1.0.0.0.0.1.1
....0.0.1.1.1.0.1.0.0
...0.0.1.0.1.0.1.1.0.0

Crossrefs

Sequence in context: A155314 A155321 A155425 * A155429 A155346 A155398

Adjacent sequences: A155407 A155408 A155409 * A155411 A155412 A155413

Keyword

nonn

Author

R. H. Hardin, Jan 22 2009

Status

approved