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 A147719 #4 Mar 30 2012 18:51:59 %S A147719 1,1,1,2,6,21,91,462,2646,16841,117931,900922,7456086,66453661, %T A147719 634585771,6463837382,69955114326,801626558481,9696295037611, %U A147719 123457062745842,1650499351041366,23116291464379301,338474628835617451 %N A147719 A141479(n+1)/3. %K A147719 nonn %O A147719 0,4 %A A147719 _Paul Curtz_, Nov 11 2008 %E A147719 More terms from _R. J. Mathar_, Jan 22 2009