%I A038055
%S A038055 2,4,14,52,214,916,4116,18996,89894,433196,2119904,10503612,52594476,
%T A038055 265713532,1352796790,6933598208,35747017596,185260197772,
%U A038055 964585369012,5043220350012,26467146038744,139375369621960
%N A038055 Number of n-node rooted trees with nodes of 2 colors.
%H A038055 <a href="Sindx_Ro.html#rooted">Index entries for sequences related to
rooted trees</a>
%H A038055 N. J. A. Sloane, <a href="transforms.txt">Transforms</a>
%H A038055 <a href="Sindx_Tra.html#trees">Index entries for sequences related to
trees</a>
%F A038055 Shifts left and halves under Euler transform. A000151*2.
%p A038055 spec := [N, {N=Prod(bead,Set(N)), bead=Union(R,B), R=Atom, B=Atom}];
[seq(combstruct[count](spec, size=n), n=1..40)];
%Y A038055 Cf. A000081, A038056-A038062.
%Y A038055 Sequence in context: A055727 A003500 A129876 this_sequence A006385 A131180
A047990
%Y A038055 Adjacent sequences: A038052 A038053 A038054 this_sequence A038056 A038057
A038058
%K A038055 nonn,eigen,nice
%O A038055 1,1
%A A038055 Christian G. Bower (bowerc(AT)usa.net), Jan 04 1999.
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