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%I #11 Mar 03 2015 00:55:56
%S 0,2,2,5,12,31,78,208,549,1490,4060,11205,31074,86862,243796,687643,
%T 1946184,5526723,15736664,44920308,128495647,368274074,1057275163,
%U 3039990187,8752947291,25233737677,72828925967,210416568930
%N Total number of leaves and roots in the planted trees of order n.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TreeLeaf.html">Tree Leaf</a>
%H W. Bomfim, <a href="http://oeis.org/wiki/File:A3.png">The nine rooted trees with five nodes</a>
%H W. Bomfim, <a href="/w/images/d/d7/CprogramA095339.txt">C program</a> around function Gen() by Gang Li & Frank Ruskey.
%e See the 12 yellow nodes in the Bomfim link. So a(5)=12.
%K nonn
%O 1,2
%A _Eric W. Weisstein_, Jun 02 2004
%E a(13)-a(28) from _Washington Bomfim_, Jan 29 2011