A153926 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 3 ones in any 5 X 5 X 5 subtriangle.

1, 2, 2, 3, 5, 6, 12, 35, 83, 231, 918, 2132, 7575, 42734, 132320, 609928, 4694085, 18109624, 113969565, 1148801096, 6065910343, 51213901318

Offset

0,2

Links

Table of n, a(n) for n=0..21.

Crossrefs

Sequence in context: A111077 A283189 A032157 * A035425 A139074 A179418

Adjacent sequences: A153923 A153924 A153925 * A153927 A153928 A153929

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved