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 A230759 #13 Mar 02 2014 08:15:59
%S A230759 2,28,259,1241,3647,14715,399301,4810319,34161842,146769868,244200526,
%T A230759 4359995640,73982566838,804676166812,4381447604821,15981352647839,
%U A230759 8477785985767,965700694136205,13070487060661219,114948480102611400,541029996598203398
%N A230759 Values of x such that x^2 + y^2 = 53^n with x and y coprime and 0 < x < y.
%C A230759 The corresponding y-values are in A230760.
%H A230759 Vincenzo Librandi, <a href="/A230759/b230759.txt">Table of n, a(n) for n = 1..200</a>
%e A230759 a(3)=259 because 259^2+286^2=148877=53^3.
%t A230759 Table[Select[PowersRepresentations[53^n, 2, 2], CoprimeQ@@#&][[1, 1]], {n, 1, 40}] (* _Vincenzo Librandi_, Mar 02 2014 *)
%Y A230759 Cf. A230760, A188948, A230622, A230644, A230710, A230712, A230743.
%K A230759 nonn
%O A230759 1,1
%A A230759 _Colin Barker_, Oct 29 2013