Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 5 which is symmetric after a rotation by 180 degrees.
A123787
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 5 which is symmetric after a rotation by 180 degrees.
Terms
- a(0) =1a(1) =2a(2) =28a(3) =192a(4) =1680a(5) =13644a(6) =118916a(7) =1044873a(8) =9160772
External references
- oeis: A123787