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 A173100 #2 Mar 31 2012 12:38:28
%S A173100 2,2,4,10,66,1244,162898,405126082,131988051722292,
%T A173100 106943604398142563191514,28230555977340642743866391573263146370,
%U A173100 6038154820760673175690853635193471535603786459126013221470476
%N A173100 a(1)=2, a(2)=2, a(n)=2*a(n-2)*a(n-1)-a(n-2)-a(n-1).
%t A173100 a=2;b=2;lst={a,b};Do[c=2*a*b-a-b;AppendTo[lst,c];a=b;b=c,{n,12}];lst
%Y A173100 Cf. A173093, A173094, A173096, A173097, A173098, A173099
%K A173100 nonn
%O A173100 1,1
%A A173100 _Vladimir Joseph Stephan Orlovsky_, Feb 09 2010