A153941 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 5 ones in any 4 X 4 X 4 subtriangle.

1, 2, 2, 3, 8, 18, 64, 323, 1239, 7677, 70851, 462347, 4699837, 77982415, 865056340, 15519583779, 437728798867, 8808271045842, 278977031301418

Offset

0,2

Links

Table of n, a(n) for n=0..18.

Crossrefs

Sequence in context: A158763 A001131 A019177 * A184844 A252848 A241475

Adjacent sequences: A153938 A153939 A153940 * A153942 A153943 A153944

Keyword

nonn

Author

R. H. Hardin Jan 03 2009

Status

approved