A153933 Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with no more than 4 ones in any 4 X 4 X 4 subtriangle.

1, 2, 4, 13, 26, 135, 581, 5081, 33999, 455470, 5028919, 110445068, 1936072745, 69174531647, 1977766145879, 114385090415133, 5299105178883837, 494911099658091565, 37117101455488584937

Offset

0,2

Links

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

Crossrefs

Sequence in context: A189583 A153936 A027301 * A128601 A034500 A261455

Adjacent sequences: A153930 A153931 A153932 * A153934 A153935 A153936

Keyword

nonn

Author

R. H. Hardin, Jan 03 2009

Status

approved