Numbers k such that 5*10^k + 9 is prime.

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =8a(5) =20a(6) =29a(7) =86a(8) =283a(9) =757a(10) =1199a(11) =2473a(12) =2733a(13) =24853a(14) =39629a(15) =53492a(16) =71237a(17) =72302a(18) =81653a(19) =167510