Primes that remain prime through 3 iterations of function f(x) = 2x + 9.

Terms

a(0) =5a(1) =11a(2) =31a(3) =71a(4) =281a(5) =521a(6) =911a(7) =1181a(8) =2371a(9) =2521a(10) =3391a(11) =3701a(12) =4211a(13) =4931a(14) =5051a(15) =7211a(16) =7411a(17) =8221a(18) =8431a(19) =8461a(20) =8501a(21) =8641a(22) =8951a(23) =9601a(24) =9871a(25) =10301a(26) =11981a(27) =12421a(28) =13121a(29) =13921