Smallest odd number with exactly n nonprime divisors.

Terms

a(0) =1a(1) =9a(2) =27a(3) =45a(4) =105a(5) =135a(6) =225a(7) =405a(8) =315a(9) =675a(10) =177147a(11) =1155a(12) =945a(13) =3375a(14) =1575a(15) =6075a(16) =2835a(17) =10125a(18) =18225a(19) =3465a(20) =4725a(21) =30375a(22) =50625a(23) =11025a(24) =25515a(25) =91125a(26) =14175a(27) =10395a(28) =23625a(29) =273375