a(n) = Sum_{1 <= x_1, x_2, ... , x_n <= n} n/gcd(x_1, x_2, ... , x_n, n).

A372969

a(n) = Sum_{1 <= x_1, x_2, ... , x_n <= n} n/gcd(x_1, x_2, ... , x_n, n).

Terms

    a(0) =1a(1) =7a(2) =79a(3) =991a(4) =15621a(5) =277495a(6) =5764795a(7) =133955071a(8) =3486666301a(9) =99951163687

External references