Numbers k such that sigma(k)/k, sigma_3(k)/k and sigma_5(k)/k are all integers.

A076231

Numbers k such that sigma(k)/k, sigma_3(k)/k and sigma_5(k)/k are all integers.

Terms

    a(0) =1a(1) =6a(2) =120a(3) =672a(4) =8128a(5) =30240a(6) =32760a(7) =33550336a(8) =459818240a(9) =1379454720a(10) =1476304896a(11) =8589869056a(12) =31998395520a(13) =51001180160a(14) =66433720320a(15) =137438691328a(16) =153003540480a(17) =403031236608

External references