A155386 Number of ways to place zero or more nonadjacent 0,0 1,0 2,0 3,0 4,0 5,0 6,0 7,0 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 10, 45, 176, 869, 4190, 22684, 124296, 729069, 4981537, 38867913, 351596326

Offset

7,2

Links

Table of n, a(n) for n=7..19.

Example

Maximal 10 X 10 X 10 example
............1
...........0.1
..........1.0.1
.........1.0.0.1
........1.0.0.0.1
.......1.0.0.0.0.1
......1.0.0.0.0.0.1
.....1.0.0.0.0.0.0.1
....1.0.0.0.0.0.0.0.0
...1.0.1.1.1.1.1.1.1.1

Crossrefs

Sequence in context: A197627 A066229 A149226 * A155330 A155278 A155237

Adjacent sequences: A155383 A155384 A155385 * A155387 A155388 A155389

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved