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arXiv · 2009.12066

A conjecture on different central parts of binary trees

Dinesh Pandey·Kamal Lochan Patra
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Abstract

Let $\Omega_n$ be the family of binary trees on $n$ vertices obtained by identifying the root of an rgood binary tree with a vertex of maximum eccentricity of a binary caterpillar. In the paper titled "On different middle parts of a tree (The electronic journal of combinatorics, 25 (2018), no. 3, paper 3.17, 32 pp)", Smith et al. conjectured that among all binary trees on $n$ vertices the pairwise distance between any two of center, centroid and subtree core is maximized by some member of the family $\Omega_n$. We first obtain the rooted binary tree which minimizes the number of root containing subtrees and then prove this conjecture. We also obtain the binary trees which maximize these distances.

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Dinesh Pandey, Kamal Lochan Patra. 2020-09-25. A conjecture on different central parts of binary trees. https://arxiv.org/abs/2009.12066

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