a(1)=9; if n = Product p_i^e_i, n > 1, then a(n) = Product p_{i+2}^{e_i+1}.

Terms

a(0) =9a(1) =25a(2) =49a(3) =125a(4) =121a(5) =1225a(6) =169a(7) =625a(8) =343a(9) =3025a(10) =289a(11) =6125a(12) =361a(13) =4225a(14) =5929a(15) =3125a(16) =529a(17) =8575a(18) =841a(19) =15125a(20) =8281a(21) =7225a(22) =961a(23) =30625a(24) =1331a(25) =9025a(26) =2401a(27) =21125a(28) =1369a(29) =148225