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 A128574 #6 Mar 19 2016 09:04:17
%S A128574 1,5,60,1020,21420,523320,14399280,437433780,14479664640,517426156800,
%T A128574 19824547680000,810083131361280,35155640625638400,1614680474921256960,
%U A128574 78256021787814850560,3991780109967777792000,213813097136418588641280
%N A128574 Row 4 of table A128570.
%H A128574 Vaclav Kotesovec, <a href="/A128574/b128574.txt">Table of n, a(n) for n = 0..360</a>
%F A128574 G.f.: A(x) = 1 + 5x*R(x,5)^2, where R(x,5) = 1 + 6*x*R(x,6)^2, R(x,6) = 1 + 7*x*R(x,7)^2, ..., R(x,n) = 1 + (n+1)*x*R(x,n+1)^2, ... and R(x,n) is the g.f. of row n of table A128570.
%F A128574 a(n) ~ 32*n^4*A128318(n)/243. - _Vaclav Kotesovec_, Mar 19 2016
%o A128574 (PARI) {a(n)=local(A=1+(n+5)*x);for(j=0,n,A=1+(n+5-j)*x*A^2 +x*O(x^n)); polcoeff(A,n)}
%Y A128574 Cf. A128570 (triangle), other rows: A128318, A128571, A128572, A128573, A128575, A128576; A128577 (square of row 0), A128578 (main diagonal), A128579 (antidiagonal sums).
%K A128574 nonn
%O A128574 0,2
%A A128574 _Paul D. Hanna_, Mar 11 2007