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Related papers: Immersions in highly edge connected graphs

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A $k$-weak bisection of a cubic graph $G$ is a partition of the vertex-set of $G$ into two parts $V_1$ and $V_2$ of equal size, such that each connected component of the subgraph of $G$ induced by $V_i$ ($i=1,2$) is a tree of at most $k-2$…

Combinatorics · Mathematics 2017-09-15 Louis Esperet , Giuseppe Mazzuoccolo , Michael Tarsi

Let $G$ be a graph on $n$ vertices. An induced subgraph $H$ of $G$ is called heavy if there exist two nonadjacent vertices in $H$ with degree sum at least $n$ in $G$. We say that $G$ is $H$-heavy if every induced subgraph of $G$ isomorphic…

Combinatorics · Mathematics 2011-09-20 Binlong Li , Zdeněk Ryjáček , Ying Wang , Shenggui Zhang

We show that every graph admits a canonical tree-like decomposition into its $k$-edge-connected pieces for all $k\in\mathbb{N}\cup\{\infty\}$ simultaneously.

Combinatorics · Mathematics 2021-05-03 Christian Elbracht , Jan Kurkofka , Maximilian Teegen

In this paper, we investigate the complexity of Maximum Independent Set (MIS) in the class of $H$-free graphs, that is, graphs excluding a fixed graph as an induced subgraph. Given that the problem remains $NP$-hard for most graphs $H$, we…

Data Structures and Algorithms · Computer Science 2019-02-21 Édouard Bonnet , Nicolas Bousquet , Pierre Charbit , Stéphan Thomassé , Rémi Watrigant

We prove that graphs that do not contain a totally odd immersion of $K_t$ are $\mathcal{O}(t)$-colorable. In particular, we show that any graph with no totally odd immersion of $K_t$ is the union of a bipartite graph and a graph which…

Combinatorics · Mathematics 2025-08-21 Caleb McFarland

For a tree decomposition $\mathcal{T}$ of a graph $G$, let $\mu(\mathcal{T})$ denote the maximum size of an induced matching in $G$ with the property that some bag of $\mathcal{T}$ contains at least one endpoint of every edge of the…

For a family $\mathcal{H}$ of graphs, a graph $G$ is said to be {\it $\mathcal{H}$-free} if $G$ contains no member of $\mathcal{H}$ as an induced subgraph. We let $\tilde{\mathcal{G}}_{3}(\mathcal{H})$ denote the family of connected…

Combinatorics · Mathematics 2024-04-18 Yoshimi Egawa , Michitaka Furuya

The Tree Decomposition Conjecture by Bar\'at and Thomassen states that for every tree $T$ there exists a natural number $k(T)$ such that the following holds: If $G$ is a $k(T)$-edge-connected simple graph with size divisible by the size of…

Combinatorics · Mathematics 2016-03-02 Martin Merker

We say that a graph $F$ can be embedded into a graph $G$ if $G$ contains an isomorphic copy of $F$ as a subgraph. Guo and Volkmann \cite{GV} conjectured that if $G$ is a connected graph with at least $n$ vertices and minimum degree at least…

Combinatorics · Mathematics 2022-01-03 Zilong Yan , Yuejian Peng

This paper is motivated by the following question: what are the unavoidable induced subgraphs of graphs with large treewidth? Aboulker et al. made a conjecture which answers this question in graphs of bounded maximum degree, asserting that…

We provide a structural description of, and invariants for, maximum spanning tree-packable graphs, i.e. those graphs G for which the edge connectivity of G is equal to the maximum number of edge-disjoint spanning trees in G. These graphs…

Combinatorics · Mathematics 2012-03-07 Robert F. Bailey , Brett Stevens

Given two graphs $G$ and $H$, we say that $G$ contains $H$ as an induced minor if a graph isomorphic to $H$ can be obtained from $G$ by a sequence of vertex deletions and edge contractions. We study the complexity of Graph Isomorphism on…

Discrete Mathematics · Computer Science 2016-05-30 Rémy Belmonte , Yota Otachi , Pascal Schweitzer

We introduce new sufficient conditions for intrinsic knotting and linking. A graph on n vertices with at least 4n-9 edges is intrinsically linked. A graph on n vertices with at least 5n-14 edges is intrinsically knotted. We also classify…

Geometric Topology · Mathematics 2007-05-23 J. Campbell , T. W. Mattman , R. Ottman , J. Pyzer , M. Rodrigues , S. Williams

The connectivity of a graph is an important parameter to evaluate its reliability. $k$-restricted connectivity (resp. $R^h$-restricted connectivity) of a graph $G$ is the minimum cardinality of a set $S$ of vertices in $G$, if exists, whose…

Computational Complexity · Computer Science 2026-01-15 Huazhong Lü , Tingzeng Wu

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

Let $\mathcal{H}$ be a class of given graphs. A graph $G$ is said to be $\mathcal{H}$-free if $G$ contains no induced copies of $H$ for any $H \in \mathcal{H}$. In this article, we characterize all pairs $\{R,S\}$ of graphs such that every…

Combinatorics · Mathematics 2017-11-27 Junfeng Du , Ziwen Huang , Liming Xiong

We consider the problem of immersing the complete digraph on t vertices in a simple digraph. For Eulerian digraphs, we show that such an immersion always exists whenever minimum degree is at least t(t-1), and for t at most 4 minimum degree…

Combinatorics · Mathematics 2011-09-20 Matt DeVos , Jessica McDonald , Bojan Mohar , Diego Scheide

The GG-width of a class of graphs GG is defined as follows. A graph G has GG-width k if there are k independent sets N1,...,Nk in G such that G can be embedded into a graph H in GG such that for every edge e in H which is not an edge in G,…

Combinatorics · Mathematics 2012-11-01 M. Chang , L. Hung , T. Kloks , S. Peng

Given graphs G and H with V(G) containing V(H), suppose that we have a u,v-path P_{uv} in G for each edge uv in H. There are obvious additional conditions that ensure that G contains H as a rooted subgraph, subdivision, or immersion; we…

Combinatorics · Mathematics 2012-07-27 André Kündgen , Michael J. Pelsmajer , Radhika Ramamurthi

An immersion of a compact manifold is tight if it admits the minimal total absolute curvature over all immersions of the manifold. A prominent result in the study of minimal total absolute curvature immersions is the theorem of Chern and…

dg-ga · Mathematics 2008-02-03 Ross Niebergall , Gudlaugur Thorbergsson