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Related papers: Stability of Critical p-Improper Interval Graphs

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We present a method which provides a unified framework for most stability theorems that have been proved in graph and hypergraph theory. Our main result reduces stability for a large class of hypergraph problems to the simpler question of…

Combinatorics · Mathematics 2022-11-15 Xizhi Liu , Dhruv Mubayi , Christian Reiher

A graph is strongly perfect if every induced subgraph H has a stable set that meets every nonempty maximal clique of H. The characterization of strongly perfect graphs by a set of forbidden induced subgraphs is not known. Here we provide…

Combinatorics · Mathematics 2020-03-05 Maria Chudnovsky , Cemil Dibek , Paul Seymour

The classic N p chart gives a signal if the number of successes in a sequence of inde- pendent binary variables exceeds a control limit. Motivated by engineering applications in industrial image processing and, to some extent, financial…

Methodology · Statistics 2010-01-13 Ansgar Steland , Ewaryst Rafalowicz

We work out the graph limit theory for dense interval graphs. The theory developed departs from the usual description of a graph limit as a symmetric function $W(x,y)$ on the unit square, with $x$ and $y$ uniform on the interval $(0,1)$.…

Combinatorics · Mathematics 2011-02-15 Persi Diaconis , Susan Holmes , Svante Janson

In the context of the chromatic-number problem, a critical graph is an instance where the deletion of any element would decrease the graph's chromatic number. Such instances have shown to be interesting objects of study for deepen the…

Discrete Mathematics · Computer Science 2017-07-13 Andreas Jakoby , Naveen Kumar Goswami , Eik List , Stefan Lucks

A graph of order $n$ is $p$-factor-critical, where $p$ is an integer of the same parity as $n$, if the removal of any set of $p$ vertices results in a graph with a perfect matching. 1-Factor-critical graphs and 2-factor-critical graphs are…

Combinatorics · Mathematics 2012-12-18 Heping Zhang , Wuyang Sun

Graph parameters such as the clique number, the chromatic number, and the independence number are central in many areas, ranging from computer networks to linguistics to computational neuroscience to social networks. In particular, the…

Computational Complexity · Computer Science 2020-12-15 Fabian Frei , Edith Hemaspaandra , Jörg Rothe

Given a graph $G$ then a subgraph $H$ is $isometric$ if, for every pair of vertices $u,v$ of $H$, we have $d_H(u,v) = d_G(u,v)$. We say a graph $G$ is $distance\ preserving\ (dp)$ if it has an isometric subgraph of every possible order up…

Combinatorics · Mathematics 2015-07-15 Emad Zahedi

A vertex or edge in a graph is critical if its deletion reduces the chromatic number of the graph by 1. We consider the problems of deciding whether a graph has a critical vertex or edge, respectively. We give a complexity dichotomy for…

Computational Complexity · Computer Science 2017-06-29 Daniël Paulusma , Christophe Picouleau , Bernard Ries

A short proof is given that the graphs with proper interval representations are the same as the graphs with unit interval representations.

Combinatorics · Mathematics 2007-05-23 Kenneth P. Bogart , Douglas B. West

A lower bound is obtained for the greatest possible number of colors in an interval colourings of some regular graphs.

Discrete Mathematics · Computer Science 2007-12-20 Rafael R. Kamalian , Petros A. Petrosyan

Vertex splitting is a graph modification operation in which a vertex is replaced by multiple vertices such that the union of their neighborhoods equals the neighborhood of the original vertex. We introduce and study vertex splitting as a…

Computational Complexity · Computer Science 2026-02-05 Faisal N. Abu-Khzam , Dipayan Chakraborty , Lucas Isenmann , Nacim Oijid

Given a graph G = (V,E), a vertex subset S is called t-stable (or t-dependent) if the subgraph G[S] induced on S has maximum degree at most t. The t-stability number of G is the maximum order of a t-stable set in G. We investigate the…

Combinatorics · Mathematics 2010-10-27 Nikolaos Fountoulakis , Ross J. Kang , Colin McDiarmid

We consider undirected simple finite graphs. The sets of vertices and edges of a graph $G$ are denoted by $V(G)$ and $E(G)$, respectively. For a graph $G$, we denote by $\delta(G)$ and $\eta(G)$ the least degree of a vertex of $G$ and the…

Combinatorics · Mathematics 2013-07-05 N. N. Davtyan , R. R. Kamalian

The graph parameter vertex integrity measures how vulnerable a graph is to a removal of a small number of vertices. More precisely, a graph with small vertex integrity admits a small number of vertex removals to make the remaining connected…

Data Structures and Algorithms · Computer Science 2024-11-01 Tatsuya Gima , Tesshu Hanaka , Yasuaki Kobayashi , Ryota Murai , Hirotaka Ono , Yota Otachi

A cocomparability graph is a graph whose complement admits a transitive orientation. An interval graph is the intersection graph of a family of intervals on the real line. In this paper we investigate the relationships between interval and…

Discrete Mathematics · Computer Science 2016-11-08 Jérémie Dusart , Michel Habib , Derek G. Corneil

An interval graph has interval count $\ell$ if it has an interval model, where among every $\ell+1$ intervals there are two that have the same length. Maximum Cut on interval graphs has been found to be NP-complete recently by Adhikary et…

Computational Complexity · Computer Science 2024-04-25 Alexey Barsukov , Bodhayan Roy

In this paper a greedy algorithm to detect conflict cliques in interval graphs and circular-arc graphs is analyzed. In a graph, a stable set requires that at most one vertex is chosen for each edge. It is equivalent to requiring that at…

Discrete Mathematics · Computer Science 2008-12-12 Gabrio Caimi , Holger Flier , Martin Fuchsberger , Marc Nunkesser

The distinguishing number $D(G)$ of a graph $G$ is the least integer $d$ such that $G$ has a vertex labeling with $d$ labels that is preserved only by a trivial automorphism. The distinguishing stability, of a graph $G$ is denoted by…

Combinatorics · Mathematics 2016-09-26 Saeid Alikhani , Samaneh Soltani

The all-terminal reliability of a graph $G$ is the probability that $G$ remains connected when each edge fails independently with probability $p$. For fixed $n$ and $m$, the uniformly most reliable problem asks which graph with $n$ vertices…

Combinatorics · Mathematics 2026-03-03 Rotem Brand , Reuven Cohen , Simi Haber , Baruch Barzel