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 A001161 #8 Sep 04 2013 05:12:57 %S A001161 0,4,5,9,11,12,13,14,18,19,20,24,25,29,30,34,35,39,41,42,43,46,47,48, %T A001161 51,52,53,56,57,58,61,62,63,66,67,68,71,72,73,76,77,78,80,84,85,89,90, %U A001161 94,95,99 %N A001161 Numbers containing an even number of letters. %Y A001161 Cf. A005589, complement of A001162. %K A001161 nonn,word %O A001161 1,2 %A A001161 William P. Everts [ bille(AT)regenisys.com ]