A155433 Number of ways to place zero or more nonadjacent 1,0 1,1 2,0 2,2 3,0 3,3 4,1 4,3 polyhexes in any orientation on a planar nXnXn triangular grid.

1, 4, 13, 28, 49, 76, 487, 3766, 20956, 91261, 385483, 3099937, 40032793, 511624885, 5661397930, 61479664849, 927273309259, 20003424034360, 509150633289499, 13132668672579046, 346049894030528596

Offset

4,2

Links

Table of n, a(n) for n=4..24.

Example

Maximal 10 X 10 X 10 example
............0
...........0.0
..........1.1.1
.........1.0.0.1
........0.0.0.1.0
.......0.0.1.1.0.0
......1.1.0.0.0.1.1
.....1.0.0.0.0.0.0.1
....1.0.0.1.0.1.0.0.1
...0.1.1.1.0.0.1.1.1.0

Crossrefs

Sequence in context: A356984 A307272 A056107 * A272746 A273557 A272790

Adjacent sequences: A155430 A155431 A155432 * A155434 A155435 A155436

Keyword

nonn

Author

R. H. Hardin Jan 22 2009

Status

approved