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 A339040 #12 Dec 02 2020 17:50:17
%S A339040 1,3,10,35,125,460,1747,6830,27502,113987,485971,2129956,9591009,
%T A339040 44341610,210345962,1023182861,5100235807,26035673051,136023990102,
%U A339040 726877123975,3970461069738,22156281667277,126234185382902,733899631974167,4351500789211840
%N A339040 Number of unlabeled connected simple graphs with n edges rooted at two noninterchangeable vertices.
%F A339040 G.f.: f(x)/g(x) - r(x)^2 where f(x), g(x) and r(x) are the g.f.'s of A339063, A000664 and A339039.
%o A339040 (PARI) \\ See A339063 for G.
%o A339040 seq(n)={my(A=O(x*x^n), g=G(2*n, x+A, [])); Vec(G(2*n, x+A, [1, 1])/g - (G(2*n, x+A, [1])/g)^2)}
%Y A339040 Cf. A000664, A002905, A303832, A304074, A339039, A339041, A339042, A339044, A339063.
%K A339040 nonn
%O A339040 1,2
%A A339040 _Andrew Howroyd_, Nov 20 2020