This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A120311 #22 Feb 10 2021 03:29:32
%S A120311 8,9,19,20,22,38,39,54,56,58,72,90,91,92,93,94,95,96,107,131,132,133,
%T A120311 153,154,155,156,173,175,177,193,195,224,225,239,240,266,281,282,311,
%U A120311 340,344,346,360,363,364,365,383,385,386,387
%N A120311 Numbers k such that pi(k) == 0 (mod 4), where pi() = A000720, and such that prime(k) == 3 (mod 4).
%t A120311 a = Flatten[Table[If[Mod[PrimePi[n], 4] == 0&& Mod[Prime[n], 4] -3 == 0, n, {}], {n, 1, 200}]]
%t A120311 Select[Range[400],Mod[PrimePi[#],4]==0&&Mod[Prime[#],4]==3&] (* _Harvey P. Dale_, Apr 17 2019 *)
%Y A120311 Cf. A000720. Intersection of A080148 and A120309.
%K A120311 nonn
%O A120311 1,1
%A A120311 _Roger L. Bagula_, Jun 20 2006
%E A120311 Edited and more terms added by _Michel Marcus_, Jun 01 2013
%E A120311 Offset corrected by _Michel Marcus_, Feb 10 2021