Smallest nonempty set S containing prime divisors of 10k+9 for each k in S.

Terms

a(0) =7a(1) =11a(2) =13a(3) =17a(4) =19a(5) =23a(6) =29a(7) =31a(8) =37a(9) =41a(10) =43a(11) =47a(12) =53a(13) =61a(14) =67a(15) =73a(16) =79a(17) =83a(18) =89a(19) =97a(20) =101a(21) =103a(22) =107a(23) =127a(24) =131a(25) =139a(26) =149a(27) =151a(28) =163a(29) =167