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

Terms

a(0) =0a(1) =1a(2) =1a(3) =16a(4) =1a(5) =252a(6) =1a(7) =64a(8) =729a(9) =100100a(10) =1a(11) =248976a(12) =1a(13) =105413700a(14) =762750a(15) =256a(16) =1a(17) =1895400a(18) =1a(19) =1280000400a(20) =1801097802a(22) =1a(23) =7963200a(24) =9765625a(26) =19683a(28) =1a(29) =677994300000a(30) =1a(31) =1024