Primes that remain prime through 3 iterations of function f(x) = 2x + 7.

Terms

a(0) =5a(1) =23a(2) =293a(3) =593a(4) =953a(5) =2063a(6) =3323a(7) =4133a(8) =4583a(9) =8243a(10) =8783a(11) =9173a(12) =9203a(13) =14723a(14) =15383a(15) =16103a(16) =16763a(17) =18413a(18) =19163a(19) =20123a(20) =25733a(21) =29453a(22) =37223a(23) =38783a(24) =39443a(25) =40253a(26) =41903a(27) =42923a(28) =44753a(29) =45863