Smallest nonempty set S containing prime divisors of 9k+4 for each k in S.

Terms

a(0) =5a(1) =7a(2) =11a(3) =13a(4) =17a(5) =19a(6) =23a(7) =29a(8) =31a(9) =37a(10) =41a(11) =43a(12) =47a(13) =53a(14) =59a(15) =61a(16) =67a(17) =71a(18) =79a(19) =83a(20) =103a(21) =107a(22) =109a(23) =127a(24) =137a(25) =157a(26) =163a(27) =173a(28) =191a(29) =197