A153923 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 3 ones in any 4 X 4 X 4 subtriangle.

1, 2, 723, 3847, 12686, 64066, 522788, 2375205, 17429033, 207659953, 1416380562, 15388271829, 267002004687, 2673537774503, 42803194029689, 1082510269366192

Offset

0,2

Links

Table of n, a(n) for n=0..15.

Crossrefs

Sequence in context: A000197 A036298 A341078 * A167440 A156008 A103169

Adjacent sequences: A153920 A153921 A153922 * A153924 A153925 A153926

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved