A153935 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 4 ones in any 5 X 5 X 5 subtriangle.

1, 2, 2, 3, 8, 6, 19, 86, 201, 747, 4737, 13222, 67580, 644447, 2591663, 18812351, 265019022, 1467585490, 15658902928, 326360337439

Offset

0,2

Links

Table of n, a(n) for n=0..19.

Crossrefs

Sequence in context: A056762 A213329 A069830 * A153944 A046652 A319860

Adjacent sequences: A153932 A153933 A153934 * A153936 A153937 A153938

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved