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相关论文: The edge-Erd\H{o}s-P\'osa property

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A classical result of Robertson and Seymour states that the set of graphs containing a fixed planar graph $H$ as a minor has the so-called Erd\H{o}s-P\'osa property; namely, there exists a function $f$ depending only on $H$ such that, for…

组合数学 · 数学 2013-08-23 Samuel Fiorini , Gwenaël Joret , David R. Wood

In 1986 Robertson and Seymour proved a generalization of the seminal result of Erd\H{o}s and P\'osa on the duality of packing and covering cycles: A graph has the Erd\H{o}s-P\'osa property for minors if and only if it is planar. In…

The packing problem and the covering problem are two of the most general questions in graph theory. The Erd\H{o}s-P\'{o}sa property characterizes the cases when the optimal solutions of these two problems are bounded by functions of each…

组合数学 · 数学 2024-12-16 Chun-Hung Liu

In the 1960s, Erd\H{o}s and P\'osa proved that there is a packing-covering duality for cycles in graphs. As part of the graph minor project, Robertson and Seymour greatly extended this: there is such a duality for $H$-expansions in graphs…

组合数学 · 数学 2019-09-25 Henning Bruhn , Felix Joos , Oliver Schaudt

We show that we can assume graphs that do not have the edge-Erd\H{o}s-P\'{o}sa property to be connected. Then we strengthen this result to $2$-connectivity under the additional assumptions of a minor-closed property and a generic…

组合数学 · 数学 2023-07-24 Raphael Steck

A famous conjecture of Erd\H{o}s and S\'os states that every graph with average degree more than $k - 1$ contains all trees with $k$ edges as subgraphs. We prove that the Erd\H{o}s-S\'os conjecture holds approximately, if the size of the…

组合数学 · 数学 2018-10-30 Václav Rozhoň

For a graph $H$, we say that $H$ has the Erd\H{o}s-P\'osa property for subdivisions with function $f$, if for every graph $G$, either $G$ contains (as a subgraph) $k+1$ pairwise disjoint subdivisions of $H$ or there exists a set $X\subseteq…

组合数学 · 数学 2025-12-29 Icey Siyi Ai , Maria Chudnovsky , Julien Codsi

Several min-max relations in graph theory can be expressed in the framework of the Erd\H{o}s-P\'osa property. Typically, this property reveals a connection between packing and covering problems on graphs. We describe some recent techniques…

离散数学 · 计算机科学 2016-12-14 Jean-Florent Raymond , Dimitrios M. Thilikos

A key feature of Simonovits' proof of the classic Erd\H{o}s-P\'osa theorem is a simple subgraph of the host graph, a frame, that determines the outcome of the theorem. We transfer this frame technique to $A$-paths. With it we deduce a…

组合数学 · 数学 2018-01-24 Henning Bruhn , Matthias Heinlein , Felix Joos

At the core of the Robertson-Seymour theory of graph minors lies a powerful structure theorem which captures, for any fixed graph H, the common structural features of all the graphs not containing H as a minor. Robertson and Seymour prove…

组合数学 · 数学 2011-12-13 R. Diestel , K. Kawarabayashi , T. Müller , P. Wollan

Let $H$ be a planar graph. By a classical result of Robertson and Seymour, there is a function $f:\mathbb{N} \to \mathbb{R}$ such that for all $k \in \mathbb{N}$ and all graphs $G$, either $G$ contains $k$ vertex-disjoint subgraphs each…

We show that subcubic graphs of treewidth at least $2500$ do not have the edge-Erd\H{o}s-P\'{o}sa property.

组合数学 · 数学 2023-06-16 Raphael Steck , Henning Bruhn

For every $r\in \mathbb{N}$, we denote by $\theta_{r}$ the multigraph with two vertices and $r$ parallel edges. Given a graph $G$, we say that a subgraph $H$ of $G$ is a model of $\theta_{r}$ in $G$ if $H$ contains $\theta_{r}$ as a…

组合数学 · 数学 2015-09-16 Jean-Florent Raymond , Ignasi Sau , Dimitrios M. Thilikos

The Erd\H{o}s-P\'osa property relates parameters of covering and packing of combinatorial structures and has been mostly studied in the setting of undirected graphs. In this note, we use results of Chudnovsky, Fradkin, Kim, and Seymour to…

离散数学 · 计算机科学 2023-06-22 Jean-Florent Raymond

We prove that for any circle graph $H$ with at least one edge and for any positive integer $k$, there exists an integer $t=t(k,H)$ so that every graph $G$ either has a vertex-minor isomorphic to the disjoint union of $k$ copies of $H$, or…

A class $\mathcal{F}$ of graphs has the induced Erd\H{o}s-P\'osa property if there exists a function $f$ such that for every graph $G$ and every positive integer $k$, $G$ contains either $k$ pairwise vertex-disjoint induced subgraphs that…

离散数学 · 计算机科学 2018-11-13 O-joung Kwon , Jean-Florent Raymond

We prove that the set of long cycles has the edge-Erd\H{o}s-P\'osa property: for every fixed integer $\ell\ge 3$ and every $k\in\mathbb{N}$, every graph $G$ either contains $k$ edge-disjoint cycles of length at least $\ell$ (long cycles) or…

组合数学 · 数学 2017-05-31 Henning Bruhn , Matthias Heinlein , Felix Joos

Let $T$ be a tree on $t$ vertices. We prove that for every positive integer $k$ and every graph $G$, either $G$ contains $k$ pairwise vertex-disjoint subgraphs each having a $T$ minor, or there exists a set $X$ of at most $t(k-1)$ vertices…

组合数学 · 数学 2025-02-25 Vida Dujmović , Gwenaël Joret , Piotr Micek , Pat Morin

We prove that the ladder with $3$~rungs and the house graph have the edge-Erd\H{o}s-P\'{o}sa property, while ladders with $14$~rungs or more have not. Additionally, we prove that the latter bound is optimal in the sense that the only known…

组合数学 · 数学 2024-04-16 Raphael Steck , Arthur Ulmer

A well-known conjecture of Erd\H{o}s and S\'os states that every graph with average degree exceeding $m-1$ contains every tree with $m$ edges as a subgraph. We propose a variant of this conjecture, which states that every graph of maximum…

组合数学 · 数学 2020-12-14 Frédéric Havet , Bruce Reed , Maya Stein , David R. Wood
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