Sum of primes = 3 mod 4 dividing n.

Terms

a(0) =0a(1) =0a(2) =3a(3) =0a(4) =0a(5) =3a(6) =7a(7) =0a(8) =3a(9) =0a(10) =11a(11) =3a(12) =0a(13) =7a(14) =3a(15) =0a(16) =0a(17) =3a(18) =19a(19) =0a(20) =10a(21) =11a(22) =23a(23) =3a(24) =0a(25) =0a(26) =3a(27) =7a(28) =0a(29) =3