Primes p such that (p+1)/2 is prime.

Terms

a(0) =3a(1) =5a(2) =13a(3) =37a(4) =61a(5) =73a(6) =157a(7) =193a(8) =277a(9) =313a(10) =397a(11) =421a(12) =457a(13) =541a(14) =613a(15) =661a(16) =673a(17) =733a(18) =757a(19) =877a(20) =997a(21) =1093a(22) =1153a(23) =1201a(24) =1213a(25) =1237a(26) =1321a(27) =1381a(28) =1453a(29) =1621