This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A281578 #21 Jul 23 2025 15:41:21 %S A281578 1,2,3,5,7,11,16,24,34,54,79,119,169,269,394,594,850 %N A281578 Maximum number of nonisomorphic root-containing subtrees of a rooted tree of order n. %C A281578 Isomorphism is understood in the rooted sense: isomorphisms have to preserve the root. %H A281578 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 A281578 Manfred Scheucher, <a href="/A281578/a281578.sage.txt">Sage Script (dynamic programming)</a> %e A281578 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 A281578 Cf. A281094. %K A281578 nonn,more %O A281578 1,2 %A A281578 _Stephan Wagner_, Jan 24 2017 %E A281578 a(16)-a(17) from _Manfred Scheucher_, Mar 11 2018