If n = Product (p_j^k_j) then a(n) = Sum (n^(pi(p_j) - 1)), where pi = A000720.

Terms

a(0) =0a(1) =1a(2) =3a(3) =1a(4) =25a(5) =7a(6) =343a(7) =1a(8) =9a(9) =101a(10) =14641a(11) =13a(12) =371293a(13) =2745a(14) =240a(15) =1a(16) =24137569a(17) =19a(18) =893871739a(19) =401a(20) =9282a(21) =234257a(22) =78310985281a(23) =25a(24) =625a(25) =11881377a(26) =27a(27) =21953a(29) =931a(31) =1