Primes of the form 12*2^n - 11.

Terms

a(0) =13a(1) =37a(2) =181a(3) =373a(4) =757a(5) =3061a(6) =6133a(7) =12277a(8) =196597a(9) =1572853a(10) =25165813a(11) =805306357a(12) =3221225461a(13) =6442450933a(14) =12884901877