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 A339044 #12 Nov 26 2020 22:25:38
%S A339044 1,2,6,18,57,188,651,2336,8719,33741,135185,559908,2394326,10557283,
%T A339044 47943126,223987316,1075455181,5301593544,26807904317,138924912857,
%U A339044 737220195148,4002876571636,22221898966507,126042573704637,729944250603862,4313430995825272
%N A339044 Number of unlabeled connected simple graphs with n edges rooted at one oriented edge.
%F A339044 G.f.: x*f(x)/((1+x)*g(x)) where f(x) is the g.f. of A339063 and g(x) is the g.f. of A000664.
%o A339044 (PARI) \\ See A339063 for G.
%o A339044 seq(n)={my(A=O(x*x^n)); Vec(G(2*n, x+A, [1, 1])/G(2*n, x+A, [])/(1+x))}
%Y A339044 Cf. A000664, A002905, A303832, A304072, A339037, A339039, A339040, A339041, A339063.
%K A339044 nonn
%O A339044 1,2
%A A339044 _Andrew Howroyd_, Nov 21 2020