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