Positive integers m with 2^(m-1)*phi(m) - 1 prime, where phi(.) is Euler's totient function.

Terms

a(0) =3a(1) =7a(2) =12a(3) =15a(4) =18a(5) =31a(6) =42a(7) =108a(8) =124a(9) =140a(10) =143a(11) =155a(12) =207a(13) =327a(14) =386a(15) =463a(16) =514a(17) =823a(18) =925a(19) =1035a(20) =1393a(21) =1425a(22) =2425a(23) =3873a(24) =5091a(25) =5314a(26) =5946a(27) =12813a(28) =14198a(29) =15823