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Maximum number of nonisomorphic root-containing subtrees of a rooted tree of order n
2

%I #19 Mar 11 2018 13:18:05

%S 1,2,3,5,7,11,16,24,34,54,79,119,169,269,394,594,850

%N Maximum number of nonisomorphic root-containing subtrees of a rooted tree of order n

%C Isomorphism is understood in the rooted sense: isomorphisms have to preserve the root.

%H Éva Czabarka, László A. Székely and Stephan Wagner, <a href="https://arxiv.org/abs/1601.00944">On the number of nonisomorphic subtrees of a tree</a>, arXiv:1601.00944 [math.CO], 2016.

%H Manfred Scheucher, <a href="/A281578/a281578.sage.txt">Sage Script (dynamic programming)</a>

%e For n=4, the unique rooted tree with two branches of order 1 and 2 respectively has a(4)=5 nonisomorphic subtrees containing the root: one each of order 1,2,4, and two of order 3. The three other rooted trees of order 4 have only four nonisomorphic subtrees.

%Y Cf. A281094.

%K nonn,more

%O 1,2

%A _Stephan Wagner_, Jan 24 2017

%E a(16)-a(17) from _Manfred Scheucher_, Mar 11 2018