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 A171206 #19 Jul 08 2025 07:46:58
%S A171206 1,1,12,348,19744,2108784,428817600,169398274624,131889504749568,
%T A171206 203937600707475456,628561895904796999680,3868208404121906515820544,
%U A171206 47571342639450113377565933568,1169589733863427138021074362433536,57499379103783344787572704263568097280,5652994168279651703590653986228287051923456
%N A171206 G.f. A(x) satisfies A(x) = 1 + x*A(2*x)^6.
%H A171206 Seiichi Manyama, <a href="/A171206/b171206.txt">Table of n, a(n) for n = 0..79</a>
%F A171206 a(0) = 1; a(n) = 2^(n-1) * Sum_{x_1, x_2, ..., x_6>=0 and x_1+x_2+...+x_6=n-1} Product_{k=1..6} a(x_k). - _Seiichi Manyama_, Jul 08 2025
%t A171206 terms = 16; A[_] = 0; Do[A[x_] = 1+x*A[2x]^6 + O[x]^terms // Normal, terms]; CoefficientList[A[x], x] (* _Stefano Spezia_, Apr 02 2025 *)
%o A171206 (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=0, n, A=1+x*subst(A, x, 2*x)^6); polcoeff(A, n)}
%Y A171206 Cf. A135867, A171200-A171205, A171207, A171208-A171211, A343439.
%Y A171206 Cf. A143049, A171195.
%K A171206 nonn
%O A171206 0,3
%A A171206 _Paul D. Hanna_, Dec 05 2009