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 A066317 #6 Mar 30 2012 17:37:12 %S A066317 1,1,1,1,2,6,25,92,341,1225,4366,15522,55312,197965,712244,2577106, %T A066317 9375361,34284972,125977465,464938190,1722817416,6407307544, %U A066317 23909159418,89491715106,335908316845,1264097675776,4768430557021 %N A066317 Number of rooted identity (asymmetric) planar trees that can be turned over. %H A066317 <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a> %F A066317 a(n)=A066316(n-1)+1. %K A066317 nonn %O A066317 1,5 %A A066317 _Christian G. Bower_, Dec 13 2001