Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3 which is symmetric after a rotation by 90 degrees.
A123834
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3 which is symmetric after a rotation by 90 degrees.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =7a(5) =10a(6) =13a(7) =50a(8) =190a(9) =292a(10) =403a(11) =1873a(12) =6982
External references
- oeis: A123834