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 A308371 #9 May 22 2019 20:59:33
%S A308371 1,1,4,12,42,135,500,1797,6885,26612,105561,423734,1726531,7101261,
%T A308371 29486169,123341520,519422274,2199966624,9365714175,40052639066,
%U A308371 171985425594,741214499791,3205096564624,13901238793616,60460193311425,263627546862787,1152207975128287
%N A308371 G.f. A(x) satisfies: A(x) = x * Product_{k>=1} 1/(1 - k*A(x^k)).
%F A308371 G.f. A(x) satisfies: A(x) = x * exp(Sum_{k>=1} Sum_{d|k} d * (d * A(x^d))^(k/d) / k).
%t A308371 terms = 27; A[_] = 0; Do[A[x_] = x Product[1/(1 - k A[x^k]), {k, 1, terms}] + O[x]^(terms + 1) // Normal, terms + 1]; CoefficientList[A[x], x] // Rest
%Y A308371 Cf. A050383, A091865, A308369, A308370, A308372.
%K A308371 nonn
%O A308371 1,3
%A A308371 _Ilya Gutkovskiy_, May 22 2019