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 A191811 #7 Apr 19 2025 19:35:16
%S A191811 1,1,2,9,58,501,5452,74211,1257414,26480393,689598502,21957924255,
%T A191811 844532153323,38719749230469,2091808065954023,131835936103587004,
%U A191811 9607988537163939224,803620426590302536069,76622443259122023510169
%N A191811 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^binomial(n+4,5).
%e A191811 G.f.: A(x) = 1 + x + 2*x^2 + 9*x^3 + 58*x^4 + 501*x^5 + 5452*x^6 +...
%e A191811 where the g.f. satisfies:
%e A191811 A(x) = 1 + x*A(x) + x^2*A(x)^6 + x^3*A(x)^21 + x^4*A(x)^56 + x^5*A(x)^126 + x^6*A(x)^252 + x^7*A(x)^462 +...+ x^n*A(x)^(n*(n+1)*(n+2)*(n+3)*(n+4)/5!) +...
%o A191811 (PARI) {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^binomial(m+4,5)));polcoeff(A,n)}
%Y A191811 Cf. A107591, A191809, A191810, A191812.
%K A191811 nonn
%O A191811 0,3
%A A191811 _Paul D. Hanna_, Jun 16 2011