A153905 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 1 one in any 5 X 5 X 5 subtriangle.

1, 2, 1, 1, 2, 1, 2, 5, 6, 9, 17, 17, 26, 58, 75, 126, 312, 396, 728, 2092, 2615, 5251, 16697, 25367, 59223, 199945, 337534, 830329, 2967422, 5495637, 14867026

Offset

0,2

Links

Table of n, a(n) for n=0..30.

Crossrefs

Sequence in context: A133087 A153919 A185286 * A327812 A319093 A228726

Adjacent sequences: A153902 A153903 A153904 * A153906 A153907 A153908

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved