A155390 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,0 4,1 5,1 6,1 7,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 19, 78, 382, 1679, 8329, 45625, 259832, 1747805, 14220936

Offset

7,2

Links

Table of n, a(n) for n=7..17.

Example

Maximal 10 X 10 X 10 example
............1
...........1.0
..........1.0.0
.........1.0.1.0
........0.1.0.1.0
.......0.1.0.0.1.0
......0.1.0.0.0.1.1
.....0.1.0.0.0.0.0.1
....0.0.0.1.1.1.1.0.1
...1.1.1.1.0.0.0.0.0.1

Crossrefs

Sequence in context: A111011 A144723 A062551 * A269784 A237436 A300556

Adjacent sequences: A155387 A155388 A155389 * A155391 A155392 A155393

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved