Number of planar n X n X n binary triangular grids symmetric both under 120 degree rotation and reflection with no more than 3 ones in any 3 X 3 X 3 subtriangle.
A153922
Number of planar n X n X n binary triangular grids symmetric both under 120 degree rotation and reflection with no more than 3 ones in any 3 X 3 X 3 subtriangle.
Terms
- a(0) =1a(1) =2a(2) =2a(3) =3a(4) =4a(5) =8a(6) =13a(7) =36a(8) =59a(9) =160a(10) =431a(11) =1207a(12) =3281a(13) =14493a(14) =40909a(15) =190825a(16) =830228a(17) =4020596a(18) =18120315a(19) =138139135a(20) =645018986a(21) =5068850751a(22) =37171002203a(23) =301985114648
External references
- oeis: A153922