Primes congruent to 1 or 2 modulo 4; or, primes of form x^2 + y^2; or, -1 is a square mod p.

Terms

a(0) =2a(1) =5a(2) =13a(3) =17a(4) =29a(5) =37a(6) =41a(7) =53a(8) =61a(9) =73a(10) =89a(11) =97a(12) =101a(13) =109a(14) =113a(15) =137a(16) =149a(17) =157a(18) =173a(19) =181a(20) =193a(21) =197a(22) =229a(23) =233a(24) =241a(25) =257a(26) =269a(27) =277a(28) =281a(29) =293