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%I #8 Feb 27 2023 11:22:45
%S 0,1,3,5,10,21,45,114,330,1045,3623,13545,53597,223085,969159
%N Number of unlabeled connected multigraphs with n edges, no cut-points and degree >= 3 at each node, loops allowed.
%F a(n) = A360871(n) + 1 for n > 1.
%e The a(3) = 3 multigraphs are:
%e - a single vertex with 3 loops;
%e - a triple edge;
%e - a single edge with a loop at each vertex.
%Y Cf. A002935, A360863, A360867, A360871.
%Y Row sums of A360870.
%K nonn,more
%O 1,3
%A _Andrew Howroyd_, Feb 27 2023