Numbers k such that 2^k-61 is prime.

Terms

a(0) =6a(1) =7a(2) =11a(3) =15a(4) =17a(5) =21a(6) =23a(7) =25a(8) =31a(9) =35a(10) =57a(11) =67a(12) =85a(13) =165a(14) =213a(15) =217a(16) =331a(17) =351a(18) =695a(19) =721a(20) =815a(21) =825a(22) =1007a(23) =1403a(24) =1725a(25) =1833a(26) =3213a(27) =4897a(28) =5657a(29) =6575