Number of Abelian cubes of length 3n over an alphabet of size 3. An Abelian cube is a string of the form x x' x'' with |x| = |x'| = |x''| and x is a permutation of x' and x''.
A141057
Number of Abelian cubes of length 3n over an alphabet of size 3. An Abelian cube is a string of the form x x' x'' with |x| = |x'| = |x''| and x is a permutation of x' and x''.
Terms
- a(0) =1a(1) =3a(2) =27a(3) =381a(4) =6219a(5) =111753a(6) =2151549a(7) =43497891a(8) =912018123a(9) =19671397617a(10) =434005899777
External references
- oeis: A141057