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Related papers: Decomposing graphs into forests

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Chernyshev, Rauch, and Rautenbach proved that every connected graph on $n$ vertices with less than $\frac{11}{5}n-\frac{18}{5}$ edges has a vertex cut that induces a forest, and conjectured that the same remains true if the graph has less…

Combinatorics · Mathematics 2025-05-27 F. Botler , Y. S. Couto , C. G. Fernandes , E. F. de Figueiredo , R. Gómez , V. F. dos Santos , C. M. Sato

In the present work we prove that given any two unicycle graphs (pseudoforests) that share the same degree sequence there is a finite sequence of 2-switches transforming one into the other such that all the graphs in the sequence are also…

Combinatorics · Mathematics 2021-03-02 Daniel A. Jaume , Adrián Pastine , Victor Schvöllner

This is a companion note to our paper 'Some advances on Sidorenko's conjecture', elaborating on a remark in that paper that the approach which proves Sidorenko's conjecture for strongly tree-decomposable graphs may be extended to a broader…

Combinatorics · Mathematics 2018-05-08 David Conlon , Jeong Han Kim , Choongbum Lee , Joonkyung Lee

Mining for trees in a graph is shown to be NP-complete.

Databases · Computer Science 2007-10-01 Jan Van den Bussche

An equitable partition of a graph $G$ is a partition of the vertex-set of $G$ such that the sizes of any two parts differ by at most one. We show that every graph with an acyclic coloring with at most $k$ colors can be equitably partitioned…

Combinatorics · Mathematics 2015-04-17 Louis Esperet , Laetitia Lemoine , Frédéric Maffray

We confirm Jones' Conjecture for subcubic graphs. Namely, if a subcubic planar graph does not contain $k+1$ vertex-disjoint cycles, then it suffices to delete $2k$ vertices to obtain a forest.

We settle the Path Decomposition Conjecture (P.D.C.) due to Tibor Gallai for minimally connected graphs, i.e. trees. We use this validity for trees and settle the P. D. C. using induction on the number of edges for all connected graphs. We…

General Mathematics · Mathematics 2011-06-06 Dhananjay P. Mehendale

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 present an easy structure theorem for graphs which do not admit an immersion of the complete graph. The theorem motivates the definition of a variation of tree decompositions based on edge cuts instead of vertex cuts which we call…

Combinatorics · Mathematics 2014-07-02 Paul Wollan

A perfect forest is a spanning forest of a connected graph $G$, all of whose components are induced subgraphs of $G$ and such that all vertices have odd degree in the forest. A perfect forest generalised a perfect matching since, in a…

Combinatorics · Mathematics 2016-12-16 Yair Caro , Josef Lauri , Christina Zarb

Given any two forests with the same degree sequence, we show in an algorithmic way that one can be transformed into the other by a sequence of 2-switches in such a way that all the intermediate graphs of the transformation are forests. We…

Combinatorics · Mathematics 2020-04-24 Daniel A. Jaume , Adrián Pastine , Victor Nicolas Schvöllner

Coverings of undirected graphs are used in distributed computing, and unfoldings of directed graphs in semantics of programs. We study these two notions from a graph theoretical point of view so as to highlight their similarities, as they…

Logic in Computer Science · Computer Science 2026-04-08 Bruno Courcelle

Given a collection of n rooted trees with depth h, we give a necessary and sufficient condition for this collection to be the collection of h-depth universal covering neighborhoods at each vertex.

Combinatorics · Mathematics 2017-12-12 Charles Bordenave , Simon Coste

As a generalization of the Edmonds arborescence packing theorem, Kamiyama--Katoh--Takizawa (2009) gave a good characterization of directed graphs that contain arc-disjoint arborescences spanning the set of vertices reachable from each root.…

Discrete Mathematics · Computer Science 2018-08-23 Tatsuya Matsuoka , Shin-ichi Tanigawa

We give a proof for sharp estimate for the number of spanning trees using linear algebra and generalize this bound to multigraphs. In addition, we show that this bound is tight for complete graphs. In addition, we give estimates for number…

Combinatorics · Mathematics 2022-12-01 K. V. Chelpanov

In this paper we study a new variant of graph arboricity, which requires all the forests to have the same number of edges (up to a difference of 1). We prove that the new variant, which we call equitable arboricity, is equivalent to…

Combinatorics · Mathematics 2017-05-04 Nathan Lhote , Mohammed Senhaji

Building on recent work by Thomassen, we show that Nash-Williams' orientation theorem, that every finite $2k$-edge-connected multigraph has a $k$-arc-connected orientation, also holds for all infinite multigraphs.

Combinatorics · Mathematics 2021-04-21 Marcel Koloschin , Max Pitz

Convolution trees, loopy belief propagation, and fast numerical p-convolution are combined for the first time to efficiently solve networks with several additive constraints between random variables. An implementation of this "convolution…

Computation · Statistics 2017-08-23 Oliver Serang

We show that if a graph admits a packing and a covering both consisting of $\lambda$ many spanning trees, where $\lambda$ is some infinite cardinal, then the graph also admits a decomposition into $\lambda$ many spanning trees. For finite…

Combinatorics · Mathematics 2024-05-27 Joshua Erde , Pascal Gollin , Atilla Joó , Paul Knappe , Max Pitz

Let $G$ be a graph on $n$ vertices. For $i\in \{0,1\}$ and a connected graph $G$, a spanning forest $F$ of $G$ is called an $i$-perfect forest if every tree in $F$ is an induced subgraph of $G$ and exactly $i$ vertices of $F$ have even…

Combinatorics · Mathematics 2021-07-09 Gregory Gutin , Anders Yeo