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 A152850 #2 Mar 30 2012 18:51:59 %S A152850 1,2,2,4,4,5,5,5,6,7,7,7,8,8,8,9,9,10,10,10,10,11,11,12,11,12,13,12, %T A152850 13,13,13,14,14,14,15,14,15,15,16,16,15,17,16,17,17,17,17,18,17,19,18, %U A152850 18,19,19,19,19 %N A152850 First differences of A152737. %K A152850 nonn %O A152850 0,2 %A A152850 _Paul Curtz_, Dec 14 2008