Primes that remain prime through 2 iterations of function f(x) = 9x + 2.

Terms

a(0) =3a(1) =11a(2) =19a(3) =31a(4) =103a(5) =109a(6) =113a(7) =131a(8) =151a(9) =173a(10) =179a(11) =239a(12) =283a(13) =313a(14) =491a(15) =521a(16) =599a(17) =619a(18) =733a(19) =739a(20) =773a(21) =929a(22) =1019a(23) =1103a(24) =1361a(25) =1439a(26) =1481a(27) =1621a(28) =1709a(29) =1741