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 A058149 #5 Mar 30 2012 17:37:11 %S A058149 2,10,47,283,2139 %N A058149 Monoids of order n with 3 idempotents, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator). %H A058149 <a href="/index/Mo#monoids">Index entries for sequences related to monoids</a> %Y A058149 Column 3 of A058147. %K A058149 nonn,more %O A058149 3,1 %A A058149 _Christian G. Bower_, Nov 14 2000