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 A026246 #4 Mar 30 2012 18:56:05 %S A026246 1,4,2,3,8,9,5,6,13,16,17,7,20,21,24,10,27,30,31,11,12,35,38,14,15,42, %T A026246 43,46,18,49,52,53,19,56,57,60,22,23,64,65,25,26,69,72,28,29,76,77,80, %U A026246 32,83,86,87,33,34,91,94,36,37,98,99,39,40 %N A026246 position of n in A026245. %K A026246 nonn %O A026246 1,2 %A A026246 _Clark Kimberling_