Primes that remain prime through 4 iterations of function f(x) = 5x + 4.

Terms

a(0) =263a(1) =1217a(2) =2141a(3) =4673a(4) =5333a(5) =6983a(6) =10973a(7) =11423a(8) =26669a(9) =27143a(10) =28697a(11) =74843a(12) =85061a(13) =101063a(14) =102647a(15) =114113a(16) =121001a(17) =133349a(18) =141623a(19) =150497a(20) =154823a(21) =199877a(22) =200183a(23) =202409a(24) =203039a(25) =207953a(26) =259697a(27) =259781a(28) =275813a(29) =280487