A155250 Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 2,2 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 7, 25, 55, 126, 1606, 18444, 121046, 869192, 17245415, 494281520, 10371088568, 228981497623, 9186375268339, 573254602567584, 35362817621154552

Offset

3,2

Comments

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

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

Links

Table of n, a(n) for n=3..18.

Example

Maximal 11 X 11 X 11 example
.............1
............1.1
...........1.0.1
..........0.0.1.0
.........1.0.0.0.1
........1.1.0.0.1.1
.......1.0.1.0.1.0.1
......0.1.0.0.0.0.1.0
.....1.0.0.0.1.1.0.0.1
....1.0.1.0.1.0.0.1.0.1
...1.1.1.0.1.1.1.0.1.1.1

Crossrefs

Sequence in context: A213390 A071778 A350156 * A155260 A155244 A155310

Adjacent sequences: A155247 A155248 A155249 * A155251 A155252 A155253

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved