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 A228233 #11 Jun 16 2017 22:28:55
%S A228233 0,1,5,7,9,11,17,21,23,27,35,37,41,47,49,55,63,69,77,83,91,97,103,109,
%T A228233 119,127,133,143,151,159,169,179,187,199,209,219,227,237,245,251,265,
%U A228233 279,287,301,311,323,335,351,367,377,385,401,419,431,441,455,469
%N A228233 Number of Gaussian primes of norm less than or equal to n in the first quadrant.
%C A228233 Include 2 times the primes (once for the real axis, once for the imaginary axis).
%C A228233 More precisely, a(n) includes all Gaussian primes (with the appropriate norms) on the first quadrant's bounding semi-axes. All such Gaussian primes occur in pairs {p, pi} (one real and one imaginary associate), where p is a classical prime of the form 4m + 3 (so p is in A002145) and p <= n. - _Rick L. Shepherd_, Jun 16 2017
%H A228233 T. D. Noe, <a href="/A228233/b228233.txt">Table of n, a(n) for n = 1..1000</a>
%t A228233 nn = 100; t = Select[Flatten[Table[a + b*I, {a, 0, nn}, {b, 0, nn}]], PrimeQ[#, GaussianIntegers -> True] &]; t2 = Table[0, {nn}]; Do[f = Ceiling[Abs[i]]; If[f <= nn, t2[[f]]++], {i, t}]; Accumulate[t2] (* _T. D. Noe_, Aug 19 2013 *)
%Y A228233 Cf. A000603 (number of Gaussian integers in the first quadrant with norm less than or equal to n).
%Y A228233 Cf. A062711 (counts the Gaussian primes on only one axis).
%Y A228233 Cf. A228232 (this sequence excluding classical primes and pure imaginary primes).
%Y A228233 Cf. A002145 (Gaussian primes that are positive integers).
%K A228233 nonn
%O A228233 1,3
%A A228233 _Olivier Gérard_, Aug 17 2013