Primes of the form x^2 + 27y^2.

Terms

a(0) =31a(1) =43a(2) =109a(3) =127a(4) =157a(5) =223a(6) =229a(7) =277a(8) =283a(9) =307a(10) =397a(11) =433a(12) =439a(13) =457a(14) =499a(15) =601a(16) =643a(17) =691a(18) =727a(19) =733a(20) =739a(21) =811a(22) =919a(23) =997a(24) =1021a(25) =1051a(26) =1069a(27) =1093a(28) =1327a(29) =1399