A155380 Number of ways to place zero or more nonadjacent 1,0 1,1 2,1 3,1 3,2 4,2 5,2 5,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 19, 40, 120, 445, 2107, 10099, 50833, 296830, 2080084, 17252149, 164656985, 1767665953, 21481633518, 300312864497

Offset

5,2

Links

Table of n, a(n) for n=5..21.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.0.0
.........1.1.1.0
........0.0.1.1.1
.......1.1.0.0.1.0
......0.1.0.0.0.0.1
.....0.1.1.0.0.1.1.1
....0.0.1.0.1.1.1.0.0
...0.0.1.1.0.1.0.0.0.0

Crossrefs

Sequence in context: A008118 A301160 A097116 * A155445 A133952 A155348

Adjacent sequences: A155377 A155378 A155379 * A155381 A155382 A155383

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved