Numbers k such that 381*2^k+1 is prime.

Terms

a(0) =3a(1) =15a(2) =17a(3) =20a(4) =21a(5) =41a(6) =44a(7) =51a(8) =113a(9) =140a(10) =179a(11) =219a(12) =249a(13) =323a(14) =461a(15) =521a(16) =671a(17) =680a(18) =692a(19) =695a(20) =716a(21) =809a(22) =825a(23) =887a(24) =897a(25) =1055a(26) =1439a(27) =1641a(28) =2873a(29) =4103