A154005 Number of planar n X n X n binary triangular grids symmetric both under 120 degree rotation and reflection with no more than 14 ones in any 5 X 5 X 5 subtriangle.

1, 2, 2, 4, 8, 15, 31, 126, 240, 943, 3992, 15073, 60221, 508875, 1923344, 15346988, 129704729, 978528991, 7823328579, 131906890104, 997545267990, 15909346537935, 268935937214485, 4056896542025441, 64868711455854407, 2187311046708551809

Offset

0,2

Links

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

Crossrefs

Sequence in context: A190820 A153999 A154002 * A222386 A222935 A279059

Adjacent sequences: A154002 A154003 A154004 * A154006 A154007 A154008

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved