A155387 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 3,0 4,0 5,0 6,0 7,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 28, 131, 616, 2619, 12958, 65721, 390933, 2891029, 23149838

Offset

6,2

Links

Table of n, a(n) for n=6..17.

Example

Maximal 10 X 10 X 10 example
............0
...........1.1
..........1.0.0
.........1.0.1.1
........1.0.0.0.1
.......1.0.0.0.0.1
......1.0.0.0.0.0.1
.....0.1.0.0.0.0.0.1
....1.0.0.0.0.0.1.0.1
...0.1.1.1.1.1.1.0.1.0

Crossrefs

Sequence in context: A155320 A155279 A155331 * A155366 A340002 A368570

Adjacent sequences: A155384 A155385 A155386 * A155388 A155389 A155390

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved