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 A171204 #19 Jul 08 2025 07:47:07
%S A171204 1,1,10,240,11280,1000080,169100832,55605632640,36058105605120,
%T A171204 46450803286978560,119290436529298554880,611727201854914747760640,
%U A171204 6268994998754867059071385600,128439243721180540266999017635840,5261899692949082390205726962630000640,431096933496167311430326245852780460769280
%N A171204 G.f. A(x) satisfies A(x) = 1 + x*A(2*x)^5.
%H A171204 Seiichi Manyama, <a href="/A171204/b171204.txt">Table of n, a(n) for n = 0..79</a>
%F A171204 a(0) = 1; a(n) = 2^(n-1) * Sum_{i, j, k, l, m>=0 and i+j+k+l+m=n-1} a(i) * a(j) * a(k) * a(l) * a(m). - _Seiichi Manyama_, Jul 08 2025
%t A171204 terms = 16; A[_] = 0; Do[A[x_] = 1 + x*A[2x]^5 + O[x]^terms // Normal, terms]; CoefficientList[A[x], x] (* _Stefano Spezia_, Apr 02 2025 *)
%o A171204 (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=1+x*subst(A, x, 2*x)^5); polcoeff(A, n)}
%Y A171204 Cf. A135867, A171200-A171203, A171205, A171206-A171211, A343439.
%Y A171204 Cf. A143048, A171194.
%K A171204 nonn
%O A171204 0,3
%A A171204 _Paul D. Hanna_, Dec 05 2009