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 A184978 #11 Mar 31 2012 10:26:42 %S A184978 2,4,6,9,11 %N A184978 The months of the Gregorian calendar of less than 31 days. %H A184978 Wikipedia, <a href="http://en.wikipedia.org/wiki/Gregorian_calendar">Gregorian calendar</a> %H A184978 <a href="/index/Ca#calendar">Index entries for sequences related to calendars</a> %Y A184978 Cf. A008685 (lengths of months in Gregorian calendar). %K A184978 nonn,fini,full %O A184978 1,1 %A A184978 _Jonathan M. Alexander_, Mar 27 2011