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 A026466 #5 Mar 30 2012 18:56:08 %S A026466 1,3,4,5,6,7,8,9,11,12,13,14,15,16,18,19,20,21,22,23,24,27,28,29,30, %T A026466 31,32,33,35,36,38,39,40,42,43,44,46,47,48,49,51,53,54,55,56,57,59,60, %U A026466 62,63,64,66,67,68,69,70,71,72,75,76 %N A026466 a(1) = 1; for n > 1, a(n) = least positive integer > a(n-1) and not a(i)^2 + a(j)^2 for 1<=i<j<=n-1. %K A026466 nonn %O A026466 1,2 %A A026466 _Clark Kimberling_