Numbers k such that (2^k + 1)/(2 - (-1)^k) is a prime.

Terms

a(0) =0a(1) =2a(2) =3a(3) =4a(4) =5a(5) =7a(6) =8a(7) =11a(8) =13a(9) =16a(10) =17a(11) =19a(12) =23a(13) =31a(14) =43a(15) =61a(16) =79a(17) =101a(18) =127a(19) =167a(20) =191a(21) =199a(22) =313a(23) =347a(24) =701a(25) =1709a(26) =2617a(27) =3539a(28) =5807a(29) =10501