Pythagorean primes: primes of the form 4*k + 1.

Terms

a(0) =5a(1) =13a(2) =17a(3) =29a(4) =37a(5) =41a(6) =53a(7) =61a(8) =73a(9) =89a(10) =97a(11) =101a(12) =109a(13) =113a(14) =137a(15) =149a(16) =157a(17) =173a(18) =181a(19) =193a(20) =197a(21) =229a(22) =233a(23) =241a(24) =257a(25) =269a(26) =277a(27) =281a(28) =293a(29) =313