Square of primes of the form 4k+1 (A002144).

Terms

a(0) =25a(1) =169a(2) =289a(3) =841a(4) =1369a(5) =1681a(6) =2809a(7) =3721a(8) =5329a(9) =7921a(10) =9409a(11) =10201a(12) =11881a(13) =12769a(14) =18769a(15) =22201a(16) =24649a(17) =29929a(18) =32761a(19) =37249a(20) =38809a(21) =52441a(22) =54289a(23) =58081a(24) =66049a(25) =72361a(26) =76729a(27) =78961a(28) =85849a(29) =97969