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A227807 Number of rooted identity trees with n nodes and exactly 3 subtrees from the root.

%I A227807 #5 Jul 31 2013 17:10:36
%S A227807 1,2,5,12,28,65,152,351,818,1907,4460,10453,24581,57922,136860,324088,
%T A227807 769188,1829282,4359048,10406106,24885240,59607192,142996100,
%U A227807 343540150,826468374,1990841497,4801534221,11593858684,28025623617,67816875039,164268161404
%N A227807 Number of rooted identity trees with n nodes and exactly 3 subtrees from the root.
%H A227807 Alois P. Heinz, <a href="/A227807/b227807.txt">Table of n, a(n) for n = 7..800</a>
%e A227807 :    o    :      o      o    :
%e A227807 :   /|\   :     /|\    /|\   :
%e A227807 :  o o o  :    o o o  o o o  :
%e A227807 :  | |    :   /| |    | |    :
%e A227807 :  o o    :  o o o    o o    :
%e A227807 :  |      :  |        |      :
%e A227807 :  o      :  o        o      :
%e A227807 :         :           |      :
%e A227807 :  n=7    :  n=8      o      :
%Y A227807 Column k=3 of A227774.
%K A227807 nonn
%O A227807 7,2
%A A227807 _Alois P. Heinz_, Jul 31 2013