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Related papers: Perfect Forests in Graphs and Their Extensions

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Given a graph $G$ and sets $\{\alpha_v~|~v \in V(G)\}$ and $\{\beta_v~|~v \in V(G)\}$ of non-negative integers, it is known that the decision problem whether $G$ contains a spanning tree $T$ such that $\alpha_v \le d_T (v) \le \beta_v $ for…

Combinatorics · Mathematics 2024-05-31 Christoph Brause , Jochen Harant , Florian Hörsch , Samuel Mohr

Let $G$ be a graph on $n$ vertices. A linear forest is a graph consisting of vertex-disjoint paths and isolated vertices. A maximum linear forest of $G$ is a subgraph of $G$ with maximum number of edges, which is a linear forest. We denote…

Combinatorics · Mathematics 2018-12-27 Xiuzhuan Duan , Jian Wang , Weihua Yang

In 1995, Koml\'os, S\'ark\"ozy and Szemer\'edi showed that every large $n$-vertex graph with minimum degree at least $(1/2 + \gamma)n$ contains all spanning trees of bounded degree. We consider a generalization of this result to loose…

Combinatorics · Mathematics 2024-05-03 Yanitsa Pehova , Kalina Petrova

In 2001, Brualdi and Hollingsworth proved that an edge-colored balanced complete bipartite graph Kn,n with a color set C = {1,2,3,..., 2n-1} has a heterochromatic spanning tree if the number of edges colored with colors in R is more than…

Combinatorics · Mathematics 2018-08-10 Kazuhiro Suzuki

The paper is devoted to sufficient conditions for the existence of vertex cuts in simple graphs, where the induced subgraph on the cut vertices belongs to a specified graph class. In particular, we show that any connected graph with $n$…

We consider the following problem: Let $H$ and $F$ be two graphs on $k$ vertices and assume $F \neq H$. We say that $H$ and $F$ are incomparable if neither $F$ nor $H$ contains the other. Let $H$ be a graph on $k$ vertices and let $G$ be a…

Combinatorics · Mathematics 2026-05-28 Yair Caro , Zsolt Tuza , Christina Zarb

A set $S$ of vertices in a graph is an open packing if (open) neighborhoods of any two distinct vertices in $S$ are disjoint. In this paper, we consider the graphs that have a unique maximum open packing. We characterize the trees with this…

Combinatorics · Mathematics 2019-01-29 Boštjan Brešar , Kirsti Kuenzel , Douglas F. Rall

Let $G$ be a graph with vertex set $V(G)$ and edge set $E(G)$. For $\alpha\in[0,1)$, we use $A_{\alpha}(G)$ and $\rho_{\alpha}(G)$ to denote the $A_{\alpha}$-matrix and the $A_{\alpha}$-spectral radius of $G$, respectively. The binding…

Combinatorics · Mathematics 2026-04-28 Sizhong Zhou , Hongxia Liu

Let $\mathbb{G}^{D}$ be the set of graphs $G(V,\, E)$ with $\left|V\right|=n$, and the degree sequence equal to $D=(d_{1},\, d_{2},\,\dots,\, d_{n})$. In addition, for $\frac{1}{2}<a<1$, we define the set of graphs with an almost given…

Probability · Mathematics 2014-02-24 Behzad Mehrdad

This paper presents the novel `uniqueness tree' algorithm, as one possible method for determining whether two finite, undirected graphs are isomorphic. We prove that the algorithm has polynomial time complexity in the worst case, and that…

Discrete Mathematics · Computer Science 2016-06-22 Jonathan Gorard

In this paper, we study the problem of detecting the presence of a planted perfect matching or spanning tree in an Erd\H{o}s--R\'enyi random graph. More precisely, we study the hypothesis testing problem where the statistician observes a…

Statistics Theory · Mathematics 2026-02-10 Louigi Addario-Berry , Omer Angel , Gábor Lugosi , Miklós Z. Rácz , Tselil Schramm

A fork is a graph obtained from $K_{1,3}$ (usually called claw) by subdividing an edge once. A graph is perfectly divisible if for each of its induced subgraph $H$, $V(H)$ can be partitioned into $A$ and $B$ such that $H[A]$ is perfect and…

Combinatorics · Mathematics 2025-04-23 Baogang Xu , Miaoxia Zhuang

Let $G$ be an undirected graph. An edge of $G$ dominates itself and all edges adjacent to it. A subset $E'$ of edges of $G$ is an edge dominating set of $G$, if every edge of the graph is dominated by some edge of $E'$. We say that $E'$ is…

Discrete Mathematics · Computer Science 2017-05-24 Min Chih Lin , Vadim Lozin , Veronica A. Moyano , Jayme L. Szwarcfiter

A graph $G$ is perfectly divisible if every induced subgraph $H$ of $G$ contains a set $X$ of vertices such that $X$ meets all largest cliques of $H$, and $X$ induces a perfect graph. The chromatic number of a perfectly divisible graph $G$…

Combinatorics · Mathematics 2025-06-19 Chính T. Hoàng

Let $G$ be a connected graph of order $n$. A spanning $k$-tree of $G$ is a spanning tree with the maximum degree at most $k$, and a spanning $k$-ended-tree of $G$ is a spanning tree at most $k$ leaves, where $k\geq2$ is an integer. This…

Combinatorics · Mathematics 2025-06-10 Jifu Lin , Zenan Du , Xinghui Zhao , Lihua You

In this paper, we study some spanning trees with bounded degree and leaf degree from eigenvalues. For any integer $k\geq2$, a $k$-tree is a spanning tree in which every vertex has degree no more than $k$. Let $T$ be a spanning tree of a…

Combinatorics · Mathematics 2024-07-29 Chang Liu , Jianping Li

We introduce the concept of Most, and Least, Compact Spanning Trees - denoted respectively by $T^*(G)$ and $T^\#(G)$ - of a simple, connected, undirected and unweighted graph $G(V, E, W)$. For a spanning tree $T(G) \in \mathcal{T}(G)$ to be…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-06-22 Gyan Ranjan , Nishant Saurabh , Amit Ashutosh

Given a graph G and an integer k, the objective of the $\Pi$-Contraction problem is to check whether there exists at most k edges in G such that contracting them in G results in a graph satisfying the property $\Pi$. We investigate the…

Data Structures and Algorithms · Computer Science 2023-07-26 Dipayan Chakraborty , R. B. Sandeep

In this paper, a new concept in graphs namely well-f-coveredness is introduced. We characterize all graphs with such property, whose maximum induced forests are of boundary order. Also we prove several propositions concerning with obtaining…

Combinatorics · Mathematics 2021-06-01 Reza Jafarpour-Golzari

We prove a conjecture of Shteiner and Shteyner stating that for a bipartite graph $G=(V,E)$, the number of forests in $G$ equals the number of degree sequences arising from its spanning subgraphs. In the process, we provide several…

Combinatorics · Mathematics 2026-03-03 Darij Grinberg , Benjamin Liber