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 A072713 #14 Aug 28 2016 13:02:48
%S A072713 1,1,1,1,1,2,3,7,43,1807,815861,147917502976,1339566593057489572791,
%T A072713 6793440021984612817314824762112917427331,
%U A072713 607759339422199886496126580428414916308278553796099069562650354036190535151
%N A072713 a(1)=a(2)=a(3)=a(4)=a(5)=1; for n>5, a(n)*a(n-5) = a(n-1)*a(n-2)*a(n-3)*a(n-4)+1.
%H A072713 Seiichi Manyama, <a href="/A072713/b072713.txt">Table of n, a(n) for n = 1..19</a>
%t A072713 nxt[{a_,b_,c_,d_,e_}]:={b,c,d,e,(b*c*d*e+1)/a}; Join[{1,1,1,1}, Transpose[ NestList[nxt,{1,1,1,1,1},15]][[5]]] (* _Harvey P. Dale_, Oct 03 2012 *)
%Y A072713 Cf. A005246, A051786.
%K A072713 nonn
%O A072713 1,6
%A A072713 _Benoit Cloitre_, Aug 07 2002