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 A064185 #5 Apr 30 2014 01:37:33
%S A064185 1,1,1,2,13,867,12001543,4909644519038939,
%T A064185 2976533007674072187623474816337374,
%U A064185 5305128832761583696023807632374530398637482018663107882637653612424699
%N A064185 a(n) = (b(n+3) * b(n-1) * a(n-1)^2 - 1) / b(n+2) where b(n) = A006720(n).
%o A064185 (PARI) {a(n) = if( n<1, n>=0, (b(n+3) * b(n-1) * a(n-1)^2 - 1) / b(n+2))}
%Y A064185 Cf. A006720.
%K A064185 nonn,easy
%O A064185 0,4
%A A064185 _Michael Somos_, Sep 20 2001