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The Steiner $k$-eccentricity of a vertex $v$ of a graph $G$ is the maximum Steiner distance over all $k$-subsets of $V(G)$ which contain $v$. In this paper Steiner $3$-eccentricity is studied on trees. Some general properties of the Steiner…

Combinatorics · Mathematics 2021-07-13 Xingfu Li , Guihai Yu , Sandi Klavžar

We study the Steiner $k$-eccentricity on trees, which generalizes the previous one in the paper [X.~Li, G.~Yu, S.~Klav\v{z}ar, On the average Steiner 3-eccentricity of trees, arXiv:2005.10319, 2020]. To support the algorithm, we achieve…

Combinatorics · Mathematics 2020-08-19 Xingfu Li , Guihai Yu , Sandi Klavžar , Jie Hu , Bo Li

The Steiner $k$-eccentricity of a vertex in graph $G$ is the maximum Steiner distance over all $k$-subsets containing the vertex. %Some general properties of the Steiner 3-eccentricity of trees are given. Let $\mathbb{T}_n$ be the set of…

Combinatorics · Mathematics 2022-05-09 Xin Liu

Various questions related to distances between vertices of simple, finite graphs are of interest to extremal graph theorists. The Steiner distance of a set of $k$ vertices is a natural generalization of the regular distance. We extend…

Combinatorics · Mathematics 2023-02-07 Hua Wang , Andrew Zhang

The Steiner $k$-eccentricity of a vertex $v$ of a graph $G$ is the maximum Steiner distance over all $k$-subsets of $V (G)$ which contain $v$. In this note, we design a linear algorithm for computing the Steiner $3$-eccentricities and the…

Data Structures and Algorithms · Computer Science 2021-02-23 Aleksandar Ilic

Given a connected graph $G=(V,E)$ and a $k$-set $S\subseteq V(G)$, the $Steiner$ $distance$ $d_{G}(S)$ of $S$ is defined as the size of a minimum tree including $S$ in $G$. The $Steiner$ $k$-$eccentricity$ of a vertex $v$ in $G$ is the…

Combinatorics · Mathematics 2025-12-01 Qingnan Zhang , Yingzhi Tian

Consider the complete graph on $n$ vertices, with edge weights drawn independently from the exponential distribution with unit mean. Janson showed that the typical distance between two vertices scales as $\log{n}/n$, whereas the diameter…

Probability · Mathematics 2015-07-20 A. Davidson , A. Ganesh

The Steiner $k$-eccentricity of a vertex $v$ of a graph $G$ is the maximum Steiner distance over all $k$-subsets of $V (G)$ which contain $v$. A linear time algorithm for calculating the Steiner $k$-eccentricity of a vertex on block graphs…

Combinatorics · Mathematics 2021-12-03 Xingfu Li , Guihai Yu , Aleksandar Ilić , Sandi Klavžar

We obtain sharp lower and upper bounds for the number of maximal (under inclusion) independent sets in trees with fixed number of vertices and diameter. All extremal trees are described up to isomorphism.

Combinatorics · Mathematics 2008-12-31 Alexander Dainiak

We study that over some types of trees with a given number of vertices, which trees minimize or maximize the total number of subtrees. Trees minimizing (resp. maximizing) the total number of subtrees usually maximize (resp. minimize) the…

Combinatorics · Mathematics 2012-04-30 Shuchao Li , Shujing Wang

The eccentricity of a vertex, $ecc_T(v) = \max_{u\in T} d_T(v,u)$, was one of the first, distance-based, tree invariants studied. The total eccentricity of a tree, $Ecc(T)$, is the sum of eccentricities of its vertices. We determine…

Combinatorics · Mathematics 2015-05-12 Heather Smith , László Székely , Hua Wang

In this paper, we study the upper bounds for discrete Steklov eigenvalues on trees via geometric quantities. For a finite tree, we prove sharp upper bounds for the first nonzero Steklov eigenvalue by the reciprocal of the size of the…

Spectral Theory · Mathematics 2022-03-10 Zunwu He , Bobo Hua

We find upper bounds for the degrees of vertices and Steiner points in Steiner Minimal Trees in the d-dimensional Banach spaces \ell_p^d independent of d. This is in contrast to Minimal Spanning Trees, where the maximum degree of vertices…

Metric Geometry · Mathematics 2008-03-05 K. J. Swanepoel

Motivated from the study of eccentricity, center, and sum of eccentricities in graphs and trees, we introduce several new distance-based global and local functions based on the smallest distance from a vertex to some leaf (called the…

Combinatorics · Mathematics 2019-01-30 Ya-Hong Chen , Hua Wang , Xiao-Dong Zhang

In their paper, Bounds on the Number of Edges in Hypertrees, G.Y. Katona and P.G.N. Szab\'o introduced a new, natural definition of hypertrees in $k$-uniform hypergraphs and gave lower and upper bounds on the number of edges. They also…

Combinatorics · Mathematics 2017-07-04 Péter G. N. Szabó

The eccentricity of a vertex $v$ in a graph $G$ is the maximum distance from $v$ to any other vertex. The vertices whose eccentricity are equal to the diameter (the maximum eccentricity) of $G$ are called peripheral vertices. In trees the…

Combinatorics · Mathematics 2019-09-02 Ya-Hong Chen , Hua Wang , Xiao-Dong Zhang

The Steiner distance of vertices in a set $S$ is the minimum size of a connected subgraph that contain these vertices. The sum of the Steiner distances over all sets $S$ of cardinality $k$ is called the Steiner $k$-Wiener index and studied…

Combinatorics · Mathematics 2020-08-06 Jie Zhang , Hua Wang , Xiao-Dong Zhang

We study the structure of trees minimizing their number of stable sets for given order $n$ and stability number $\alpha$. Our main result is that the edges of a non-trivial extremal tree can be partitioned into $n-\alpha$ stars, each of…

Combinatorics · Mathematics 2024-03-11 Véronique Bruyère , Gwenaël Joret , Hadrien Mélot

Let $T$ be an $n$-node tree of maximum degree 4, and let $P$ be a set of $n$ points in the plane with no two points on the same horizontal or vertical line. It is an open question whether $T$ always has a planar drawing on $P$ such that…

Computational Geometry · Computer Science 2017-09-06 Therese Biedl , Timothy M. Chan , Martin Derka , Kshitij Jain , Anna Lubiw

A vertex set $S$ is a generalized $k$-independent set if the induced subgraph $G[S]$ contains no tree on $k$ vertices. The generalized $k$-independence number $\alpha_k(G)$ is the maximum size of such a set. For a tree $T$ with $n$…

Combinatorics · Mathematics 2025-09-17 Jing Huang , Jiaxin Tang
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