Numbers k such that k^2 + 4 is prime.

Terms

a(0) =1a(1) =3a(2) =5a(3) =7a(4) =13a(5) =15a(6) =17a(7) =27a(8) =33a(9) =35a(10) =37a(11) =45a(12) =47a(13) =57a(14) =65a(15) =67a(16) =73a(17) =85a(18) =87a(19) =95a(20) =97a(21) =103a(22) =115a(23) =117a(24) =125a(25) =135a(26) =137a(27) =147a(28) =155a(29) =163