Number of subgroups of index n in fundamental group of a certain fiber space.

A027839

Number of subgroups of index n in fundamental group of a certain fiber space.

Terms

    a(0) =1a(1) =15a(2) =124a(3) =2431a(4) =68766a(5) =3025596a(6) =173773496a(7) =12786773247

External references