a(n) = Sum_{p|n, p prime} n^phi(n/p).

Terms

a(0) =0a(1) =2a(2) =3a(3) =4a(4) =5a(5) =42a(6) =7a(7) =64a(8) =81a(9) =10010a(10) =11a(11) =288a(12) =13a(13) =7529550a(14) =50850a(15) =65536a(16) =17a(17) =34012548a(18) =19a(19) =160400a(20) =85766562a(22) =23a(23) =663552a(24) =390625a(26) =387420489a(27) =481891088a(28) =29a(29) =656100810900a(30) =31