a(n) = Product_{d|n} A019565(phi(d)), where phi is Euler totient function A000010.

Terms

a(0) =2a(1) =4a(2) =6a(3) =12a(4) =10a(5) =36a(6) =30a(7) =60a(8) =90a(9) =100a(10) =42a(11) =540a(12) =70a(13) =900a(14) =210a(15) =420a(16) =22a(17) =8100a(18) =66a(19) =2100a(20) =3150a(21) =1764a(22) =330a(23) =18900a(24) =550a(25) =4900a(26) =2970a(27) =94500a(28) =770a(29) =44100