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 A024798 #3 Mar 30 2012 18:55:59 %S A024798 2,5,6,8,11,12,13,16,18,20,21,23,25,27,28,30,33,34,38,40,42,44,45,47, %T A024798 49,51,53,55,56,57,59,62,63,65,68,69,71,73,75,77,79,81,82,84,87,90,92, %U A024798 93,95,97,99,100,102,105,106,108,111,113,115,117,118,120,122,124,125,127,129,131,132 %N A024798 Positions of even numbers in A000408. %K A024798 nonn %O A024798 1,1 %A A024798 _Clark Kimberling_