Numbers k such that 7*2^k+1 is prime.

Terms

a(0) =2a(1) =4a(2) =6a(3) =14a(4) =20a(5) =26a(6) =50a(7) =52a(8) =92a(9) =120a(10) =174a(11) =180a(12) =190a(13) =290a(14) =320a(15) =390a(16) =432a(17) =616a(18) =830a(19) =1804a(20) =2256a(21) =6614a(22) =13496a(23) =15494a(24) =16696a(25) =22386a(26) =54486a(27) =88066a(28) =95330a(29) =207084