a(n) = Product_{d|n, d<n} A019565(A304759(d)).

Terms

a(0) =1a(1) =2a(2) =2a(3) =2a(4) =2a(5) =6a(6) =2a(7) =6a(8) =6a(9) =12a(10) =2a(11) =18a(12) =2a(13) =2a(14) =36a(15) =90a(16) =2a(17) =180a(18) =2a(19) =180a(20) =6a(21) =4a(22) =2a(23) =810a(24) =12a(25) =10a(26) =180a(27) =30a(28) =2a(29) =180