Squares of odd primes and twice squares of odd primes.

Terms

a(0) =9a(1) =18a(2) =25a(3) =49a(4) =50a(5) =98a(6) =121a(7) =169a(8) =242a(9) =289a(10) =338a(11) =361a(12) =529a(13) =578a(14) =722a(15) =841a(16) =961a(17) =1058a(18) =1369a(19) =1681a(20) =1682a(21) =1849a(22) =1922a(23) =2209a(24) =2738a(25) =2809a(26) =3362a(27) =3481a(28) =3698a(29) =3721