Let M be the n-th Giuga number (see A007850); a(n) = sum of (M/p - 1)/p for primes p dividing M.

A270815

Let M be the n-th Giuga number (see A007850); a(n) = sum of (M/p - 1)/p for primes p dividing M.

Terms

    a(0) =11a(1) =321a(2) =657a(3) =24699a(4) =824438641a(5) =9331106993

External references