A120311 Numbers k such that pi(k) == 0 (mod 4), where pi() = A000720, and such that prime(k) == 3 (mod 4).

8, 9, 19, 20, 22, 38, 39, 54, 56, 58, 72, 90, 91, 92, 93, 94, 95, 96, 107, 131, 132, 133, 153, 154, 155, 156, 173, 175, 177, 193, 195, 224, 225, 239, 240, 266, 281, 282, 311, 340, 344, 346, 360, 363, 364, 365, 383, 385, 386, 387

Offset: 1

Author

Roger L. Bagula, Jun 20 2006

Keywords

• nonn

Crossrefs

Cf. A000720. Intersection of A080148 and A120309.

Programs

Mathematica

a = Flatten[Table[If[Mod[PrimePi[n], 4] == 0&& Mod[Prime[n], 4] -3 == 0, n, {}], {n, 1, 200}]]
Select[Range[400],Mod[PrimePi[#],4]==0&&Mod[Prime[#],4]==3&] (* Harvey P. Dale, Apr 17 2019 *)

Extensions

Edited and more terms added by Michel Marcus, Jun 01 2013

Offset corrected by Michel Marcus, Feb 10 2021