Primes p such that p+2 and 2p+1 are also prime.

Terms

a(0) =3a(1) =5a(2) =11a(3) =29a(4) =41a(5) =179a(6) =191a(7) =239a(8) =281a(9) =419a(10) =431a(11) =641a(12) =659a(13) =809a(14) =1019a(15) =1031a(16) =1049a(17) =1229a(18) =1289a(19) =1451a(20) =1481a(21) =1931a(22) =2129a(23) =2141a(24) =2339a(25) =2549a(26) =2969a(27) =3299a(28) =3329a(29) =3359