Sophie Germain primes p: 2p+1 is also prime.

Terms

a(0) =2a(1) =3a(2) =5a(3) =11a(4) =23a(5) =29a(6) =41a(7) =53a(8) =83a(9) =89a(10) =113a(11) =131a(12) =173a(13) =179a(14) =191a(15) =233a(16) =239a(17) =251a(18) =281a(19) =293a(20) =359a(21) =419a(22) =431a(23) =443a(24) =491a(25) =509a(26) =593a(27) =641a(28) =653a(29) =659