A153984 Number of planar n X n X n binary triangular grids symmetric both under 120 degree rotation and reflection with every one adjacent to exactly 1 other one.

1, 1, 1, 1, 1, 2, 3, 2, 6, 7, 11, 23, 54, 60, 238, 445, 901, 2706, 9076, 14494, 80321, 212453, 613603, 2681494, 12847248, 29154102, 230660451, 862931932, 3568146072, 22105400251, 150948368093, 488469303948, 5510650176739, 29467826406958

Offset

0,6

Links

Table of n, a(n) for n=0..33.

Crossrefs

Sequence in context: A208611 A209582 A158279 * A025502 A110777 A087454

Adjacent sequences: A153981 A153982 A153983 * A153985 A153986 A153987

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved