A153932 Number of planar n X n X n binary triangular grids symmetric under 120 degree rotation with no more than 4 ones in any 4 X 4 X 4 subtriangle.

1, 2, 2, 3, 8, 13, 39, 225, 564, 2858, 24012, 101231, 758165, 10608857, 69903886, 854166606, 19155776749, 207379552763, 4126912621572

Offset

0,2

Links

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

Crossrefs

Sequence in context: A076541 A227380 A159789 * A158763 A001131 A019177

Adjacent sequences: A153929 A153930 A153931 * A153933 A153934 A153935

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved