a(n) = Product_{d|n, d>1} prime(A304101(d)-1).

Terms

a(0) =1a(1) =2a(2) =2a(3) =6a(4) =2a(5) =20a(6) =3a(7) =12a(8) =10a(9) =20a(10) =3a(11) =420a(12) =2a(13) =30a(14) =20a(15) =60a(16) =11a(17) =300a(18) =11a(19) =420a(20) =12a(21) =30a(22) =5a(23) =4200a(24) =22a(25) =20a(26) =130a(27) =990a(28) =3a(29) =11000