A153999 Number of planar n X n X n binary triangular grids symmetric both under 120 degree rotation and reflection with no more than 12 ones in any 5 X 5 X 5 subtriangle.

1, 2, 2, 4, 8, 15, 30, 113, 226, 897, 3372, 13821, 54535, 410690, 1677109, 13057708, 99242206, 798041029, 6266181287, 94041421473, 762970233334, 11832424270090, 179170668019138, 2871889457030716, 44959471542344339, 1344474186700872579

Offset

0,2

Links

Table of n, a(n) for n=0..25.

Crossrefs

Sequence in context: A300998 A098788 A190820 * A154002 A154005 A222386

Adjacent sequences: A153996 A153997 A153998 * A154000 A154001 A154002

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved