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 A208897 #6 Mar 30 2012 18:37:37
%S A208897 1,1,1,3,19,201,3106,64522,1704795,55095601,2115975655,94466053541,
%T A208897 4818194778101,276874057979927,17721751093252740,1251476983229057488,
%U A208897 96724943665929684251,8125833302851782601185,737619034028749204655009,71975174880203583395021875
%N A208897 A diagonal of rectangular table A208896: a(n) = A208896(n+1,n).
%C A208897 The g.f. of row n, R(n,x), in the rectangular table A208896 satisfies:
%C A208897 (1) R(n,x) = 1 + x*R(n,x)^n * [d/dx x/R(n,x)] for n>=0.
%C A208897 (2) [x^k] R(n,x)^(k-n+1) = [x^k] R(n,x)^(k-n) for k>=2.
%C A208897 The main diagonal in A208896 obeys: A208896(n,n) = 0 for n>=2.
%o A208897 (PARI) {a(n)=local(ROW=1+x+x*O(x^n));for(i=0,n,ROW=1+x*ROW^(n+1)*deriv(x/ROW));polcoeff(ROW,n)}
%o A208897 for(n=0,21,print1(a(n),","))
%Y A208897 Cf. A208896, A208898.
%K A208897 nonn
%O A208897 0,4
%A A208897 _Paul D. Hanna_, Mar 03 2012