Numbers k such that sigma(k) = 2*k + 4*phi(k).

A392692

Numbers k such that sigma(k) = 2*k + 4*phi(k).

Terms

    a(0) =7320a(1) =19488a(2) =44856a(3) =221088a(4) =1365984a(5) =252204288a(6) =16817548050

External references