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 A137964 #10 Mar 03 2018 13:52:52
%S A137964 1,1,4,26,184,1451,12020,103734,921132,8364877,77317704,725029730,
%T A137964 6880482816,65955731874,637703938860,6211709281162,60900108419200,
%U A137964 600486291654444,5950951929703520,59242473406384472,592166933647780576
%N A137964 G.f. satisfies A(x) = 1 + x*(1 + x*A(x)^5)^4.
%H A137964 Vaclav Kotesovec, <a href="/A137964/b137964.txt">Table of n, a(n) for n = 0..350</a>
%F A137964 G.f.: A(x) = 1 + x*B(x)^4 where B(x) is the g.f. of A137965.
%F A137964 a(n) = Sum_{k=0..n-1} C(4*(n-k),k)/(n-k) * C(5*k,n-k-1) for n>0 with a(0)=1. - _Paul D. Hanna_, Jun 16 2009
%F A137964 a(n) ~ sqrt(4*s*(1-s)*(5-6*s) / ((190*s - 160)*Pi)) / (n^(3/2) * r^n), where r = 0.0927175295193852172913829423030505161354091369581... and s = 1.270497495855793662015513509713357933752729700697... are real roots of the system of equations s = 1 + r*(1 + r*s^5)^4, 20 * r^2 * s^4 * (1 + r*s^5)^3 = 1. - _Vaclav Kotesovec_, Nov 22 2017
%o A137964 (PARI) {a(n)=local(A=1+x*O(x^n));for(i=0,n,A=1+x*(1+x*A^5)^4);polcoeff(A,n)}
%o A137964 (PARI) a(n)=if(n==0,1,sum(k=0,n-1,binomial(4*(n-k),k)/(n-k)*binomial(5*k,n-k-1))) \\ _Paul D. Hanna_, Jun 16 2009
%Y A137964 Cf. A137965, A137963; A137956, A137958, A137971.
%K A137964 nonn
%O A137964 0,3
%A A137964 _Paul D. Hanna_, Feb 26 2008