Numbers k such that 193*2^k-1 is prime.

Terms

a(0) =3a(1) =15a(2) =27a(3) =63a(4) =87a(5) =135a(6) =543a(7) =1383a(8) =1455a(9) =7767a(10) =18543a(11) =22143a(12) =40967a(13) =198719a(14) =405483a(15) =439107a(16) =880287