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

Terms

a(0) =0a(1) =1a(2) =1a(3) =4a(4) =1a(5) =42a(6) =1a(7) =64a(8) =81a(9) =1010a(10) =1a(11) =1872a(12) =1a(13) =38430a(14) =3600a(15) =65536a(16) =1a(17) =110808a(18) =1a(19) =160400a(20) =194922a(21) =5153654a(22) =1a(23) =8294400a(24) =15625a(25) =308915802a(26) =531441a(27) =481891088a(28) =1a(29) =729837000