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A227808 Number of rooted identity trees with n nodes and exactly 4 subtrees from the root.

%I A227808 #5 Jul 31 2013 17:11:26
%S A227808 2,4,13,34,91,225,571,1403,3466,8468,20703,50389,122673,298090,724433,
%T A227808 1759595,4274819,10385533,25240007,61358410,149226407,363077813,
%U A227808 883818374,2152462147,5244790003,12786162151,31187100089,76108058977,185825963102,453940832229
%N A227808 Number of rooted identity trees with n nodes and exactly 4 subtrees from the root.
%H A227808 Alois P. Heinz, <a href="/A227808/b227808.txt">Table of n, a(n) for n = 11..800</a>
%e A227808 :        o            o      :
%e A227808 :      /( )\        /( )\    :
%e A227808 :     / | | \      / | | \   :
%e A227808 :    o  o o  o    o  o o  o  :
%e A227808 :   /|  | |       |  | |     :
%e A227808 :  o o  o o       o  o o     :
%e A227808 :  |    |         |  |       :
%e A227808 :  o    o         o  o       :
%e A227808 :                 |          :
%e A227808 :  n=11           o          :
%Y A227808 Column k=4 of A227774.
%K A227808 nonn
%O A227808 11,1
%A A227808 _Alois P. Heinz_, Jul 31 2013