Primes of the form 1000*k + 1.

Terms

a(0) =3001a(1) =4001a(2) =7001a(3) =9001a(4) =13001a(5) =16001a(6) =19001a(7) =21001a(8) =24001a(9) =28001a(10) =51001a(11) =54001a(12) =55001a(13) =61001a(14) =69001a(15) =70001a(16) =76001a(17) =81001a(18) =88001a(19) =90001a(20) =93001a(21) =96001a(22) =97001a(23) =102001a(24) =103001a(25) =109001a(26) =114001a(27) =115001a(28) =121001a(29) =123001