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Related papers: Spanning trees with few branch vertices

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Given a graph, we can form a spanning forest by first sorting the edges in some order, and then only keep edges incident to a vertex which is not incident to any previous edge. The resulting forest is dependent on the ordering of the edges,…

Combinatorics · Mathematics 2018-02-16 Steve Butler , Misa Hamanaka , Marie Hardt

Let $k\ge 2$ be an integer and $T_1,\ldots, T_k$ be spanning trees of a graph $G$. If for any pair of vertices $(u,v)$ of $V(G)$, the paths from $u$ to $v$ in each $T_i$, $1\le i\le k$, do not contain common edges and common vertices,…

Discrete Mathematics · Computer Science 2014-09-23 Benoit Darties , Nicolas Gastineau , Olivier Togni

We introduce and study the general problem of finding a most "scale-free-like" spanning tree of a connected graph. It is motivated by a particular problem in epidemiology, and may be useful in studies of various dynamical processes in…

Combinatorics · Mathematics 2023-07-12 Yury Orlovich , Kirill Kukharenko , Volker Kaibel , Pavel Skums

The search of spanning trees with interesting disjunction properties has led to the introduction of edge-disjoint spanning trees, independent spanning trees and more recently completely independent spanning trees. We group together these…

Discrete Mathematics · Computer Science 2017-02-28 Benoit Darties , Nicolas Gastineau , Olivier Togni

Previous studies has shown that for a weighted undirected graph having $n$ vertices and $m$ edges, a minimal weight spanning tree can be found with $O^*(\sqrt{mn})$ calls to the weight oracle. The present note shows that a given spanning…

Quantum Physics · Physics 2011-12-07 Mark Heiligman

We show that a graph $G$ has a normal spanning tree if and only if its vertex set is the union of countably many sets each separated from any subdivided infinite clique in $G$ by a finite set of vertices. This proves a conjecture by Brochet…

Combinatorics · Mathematics 2020-03-27 Max Pitz

In a graph, a spanning tree is said to be a tree t-spanner of the graph if the distance between any two vertices in is at most times their distance in . The tree t-spanner has many applications in networks and distributed environments. In…

Discrete Mathematics · Computer Science 2014-08-12 Sambhu Charan Barman , Sukumar Mondal , Madhumangal Pal

Completely independent spanning trees in a graph $G$ are spanning trees of $G$ such that for any two distinct vertices of $G$, the paths between them in the spanning trees are pairwise edge-disjoint and internally vertex-disjoint. In this…

Combinatorics · Mathematics 2022-09-21 Toru Hasunuma

We present a polynomial time algorithm that for any graph G and integer k >= 0, either finds a spanning tree with at least k internal vertices, or outputs a new graph G' on at most 3k vertices and an integer k' such that G has a spanning…

Data Structures and Algorithms · Computer Science 2012-03-06 Fedor V. Fomin , Serge Gaspers , Saket Saurabh , Stéphan Thomassé

We prove that there is $c>0$ such that for all sufficiently large $n$, if $T_1,\dots,T_n$ are any trees such that $T_i$ has $i$ vertices and maximum degree at most $cn/\log n$, then $\{T_1,\dots,T_n\}$ packs into $K_n$. Our main result…

Combinatorics · Mathematics 2022-06-22 Peter Allen , Julia Böttcher , Dennis Clemens , Jan Hladký , Diana Piguet , Anusch Taraz

In this paper we give an exact analytical expression for the number of spanning trees of an infinite family of outerplanar, small-world and self-similar graphs. This number is an important graph invariant related to different topological…

Combinatorics · Mathematics 2015-06-11 Francesc Comellas , Alicia Miralles , Hongxiao Liu , Zhongzhi Zhang

The number of spanning trees in a class of directed circulant graphs with generators depending linearly on the number of vertices $\beta n$, and in the $n$-th and $(n-1)$-th power graphs of the $\beta n$-cycle are evaluated as a product of…

Combinatorics · Mathematics 2016-08-01 Justine Louis

The status of a vertex $v$ in a connected graph is the sum of the distances from $v$ to all other vertices. The status sequence of a connected graph is the list of the statuses of all the vertices of the graph. In this paper we investigate…

Combinatorics · Mathematics 2020-02-03 Aida Abiad , Boris Brimkov , Alexander Grigoriev

We suggest two related conjectures dealing with the existence of spanning irregular subgraphs of graphs. The first asserts that any $d$-regular graph on $n$ vertices contains a spanning subgraph in which the number of vertices of each…

Combinatorics · Mathematics 2021-08-09 Noga Alon , Fan Wei

Perhaps the very first elementary exercise one encounters in graph theory is the result that any graph on at least two vertices must have at least two vertices with the same degree. There are various ways in which this result can be…

Combinatorics · Mathematics 2018-06-22 Yair Caro , Josef Lauri , Christina Zarb

A dissociation set of a graph is a set of vertices which induces a subgraph with maximum degree less than or equal to one. The dissociation number of a graph is the maximum cardinality of its dissociation sets. In this paper, we study the…

Combinatorics · Mathematics 2023-09-28 Zejun Huang , Jiahui Liu , Xinwei Zhang

We consider the polyhedral properties of two spanning tree problems with additional constraints. In the first problem, it is required to find a tree with a minimum sum of edge weights among all spanning trees with the number of leaves less…

Combinatorics · Mathematics 2018-02-16 Vladimir Bondarenko , Andrei Nikolaev , Dzhambolet Shovgenov

In 2009, Kyaw proved that every $n$-vertex connected $K_{1,4}$-free graph $G$ with $\sigma_4(G)\geq n-1$ contains a spanning tree with at most $3$ leaves. In this paper, we prove an analogue of Kyaw's result for connected $K_{1,5}$-free…

Combinatorics · Mathematics 2018-10-22 Yuan Chen , Pham Hoang Ha , Dang Dinh Hanh

An $n$-vertex graph is degree 3-critical if it has $2n - 2$ edges and no proper induced subgraph with minimum degree at least 3. In 1988, Erd\H{o}s, Faudree, Gy\'arf\'as, and Schelp asked whether one can always find cycles of all short…

Combinatorics · Mathematics 2026-03-05 Francesco Di Braccio , Kyriakos Katsamaktsis , Jie Ma , Alexandru Malekshahian , Ziyuan Zhao

Given points in Euclidean space of arbitrary dimension, we prove that there exists a spanning tree having no vertices of degree greater than 3 with weight at most 1.559 times the weight of the minimum spanning tree. We also prove that there…

Computational Geometry · Computer Science 2014-07-18 Samuel Zbarsky