A153938 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 5 ones in any 3 X 3 X 3 subtriangle.

1, 2, 2, 3, 15, 24, 95, 901, 2926, 22625, 415047, 2632895, 39794767, 1442122393, 17977314936, 535815289761, 38169625321927, 935805308861487, 54839755115620718, 7680772354691458379, 370282826884218784372

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Crossrefs

Sequence in context: A275565 A275090 A274983 * A060790 A109843 A341768

Adjacent sequences: A153935 A153936 A153937 * A153939 A153940 A153941

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved