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 A050125 #4 Mar 30 2012 18:57:01 %S A050125 1,2,6,3,17,7,14,4,11,18,108,8,55,15,175,5,92,12,182,19,69,109,149,9, %T A050125 26,56,86,16,146,176,206,23,63,93,113,13,163,183,213,20,50,70,90,110, %U A050125 130,150,170,10,210,27,37,57,77,87,107,117,137 %N A050125 a(n)=position of n in A050124. %K A050125 nonn %O A050125 1,2 %A A050125 _Clark Kimberling_