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%I #7 Jun 15 2020 06:58:42
%S 1,2,10,40,187,854,4074,19602,96035,475492,2380042,12015368,61130186,
%T 313081232,1612967974,8353387992,43464071199,227101948596,
%U 1191127734498,6268882232536,33096647906860,175236408484988,930271133498794,4950509216635406,26403755607304762,141119182968584618
%N The number of mixed trees with n nodes and n-2 arcs.
%C Mixed trees are trees where a subset of the edges are directed (edges called arcs then). This is the first subdiagonal of A335362: n nodes implies trees with n-1 edges. If exactly one of these edges is not directed and the remaining n-2 edges are directed, the trees are counted here.
%H <a href="/index/Tra#trees">Index entries for sequences related to trees</a>
%F O.g.f. ( B(x)^2+B(x^2) )/2 where B(x) is the o.g.f. of A000151.
%F a(n) = A335362(n,n-2).
%Y Cf. A335362.
%K nonn
%O 2,2
%A _R. J. Mathar_, Jun 15 2020