Product of odd prime anti-factors < n, with multiplicity.

Terms

a(0) =1a(1) =1a(2) =1a(3) =9a(4) =9a(5) =1a(6) =15a(7) =15a(8) =1a(9) =21a(10) =21a(11) =25a(12) =675a(13) =27a(14) =1a(15) =33a(16) =1155a(17) =35a(18) =39a(19) =39a(20) =1a(21) =45a(22) =45a(23) =49a(24) =2499a(25) =51a(26) =55a(27) =3135a(28) =57a(29) =1