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%I #7 Jun 11 2018 14:29:04
%S 1,1,3,6,15,32,77,172,405,930,2180,5070,11914,27929,65829,155202,
%T 367053,868990,2061723,4897502,11652547,27757960,66210042,158103242,
%U 377957299,904439542,2166408422,5193894809,12463003846,29929966312,71933014935,173009938416
%N Number of unlabeled forests of rooted trees with 2n edges and n connected components, in which the outdegree of each node is <= 2 and the symmetric group acts on the components.
%H Alois P. Heinz, <a href="/A305839/b305839.txt">Table of n, a(n) for n = 0..400</a>
%F a(n) = A088326(2n,n) = A088326(2n+k,n+k) for k >= 0.
%Y Cf. A088326.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Jun 11 2018