Number of planar n X n X n binary triangular grids symmetric under 120-degree rotation with no more than 1 one in any 2 X 2 X 2 subtriangle.

A153896

Number of planar n X n X n binary triangular grids symmetric under 120-degree rotation with no more than 1 one in any 2 X 2 X 2 subtriangle.

Terms

    a(0) =1a(1) =2a(2) =1a(3) =2a(4) =6a(5) =6a(6) =12a(7) =54a(8) =68a(9) =200a(10) =1266a(11) =2320a(12) =9256a(13) =81946a(14) =206828a(15) =1160264a(16) =14343496a(17) =50776328a(18) =396238264a(19) =6835424230a(20) =33707147400a(21) =367462965472

External references