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Related papers: On the Structure of $\alpha $-Stable Graphs

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A maximum stable set in a graph G is a stable set of maximum size. S is a local maximum stable set if it is a maximum stable set of the subgraph of G spanned by the union of S and N(S), where N(S) is the neighborhood of S. A matching M is…

Combinatorics · Mathematics 2007-05-23 Vadim E. Levit , Eugen Mandrescu

A set S is independent in a graph G if no two vertices from S are adjacent. By core(G) we mean the intersection of all maximum independent sets. The independence number alpha(G) is the cardinality of a maximum independent set, while mu(G)…

Discrete Mathematics · Computer Science 2011-02-24 Vadim E. Levit , Eugen Mandrescu

A proper vertex coloring of a graph is a mapping of its vertices on a set of colors, such that two adjacent vertices are not mapped to the same color. This constraint may be interpreted in terms of the distance between to vertices and so a…

Combinatorics · Mathematics 2017-11-10 Sebastian Wiederrecht

One theorem of Nemhauser and Trotter ensures that, under certain conditions, a stable set of a graph G can be enlarged to a maximum stable set of this graph. For example, any stable set consisting of only simplicial vertices is contained in…

Combinatorics · Mathematics 2007-05-23 Vadim E. Levit , Eugen Mandrescu

A graph $\Gamma$ is said to be stable if $\mathrm{Aut}(\Gamma\times K_2)\cong\mathrm{Aut}(\Gamma)\times \mathbb{Z}_{2}$ and unstable otherwise. If an unstable graph is connected, non-bipartite and any two of its distinct vertices have…

Combinatorics · Mathematics 2025-08-04 Junyang Zhang

A b-coloring of a graph is a proper coloring such that every color class contains a vertex that is adjacent to all other color classes. The b-chromatic number of a graph G, denoted by \chi_b(G), is the maximum number t such that G admits a…

Computational Complexity · Computer Science 2023-04-04 Flavia Bonomo , Oliver Schaudt , Maya Stein , Mario Valencia-Pabon

This paper delves into the stability of the $2$-domination number in simple undirected graphs. The $2$-domination number of a graph $G$, $\gamma_2(G)$, represents the minimum size of a vertex subset where every other vertex in the graph is…

Combinatorics · Mathematics 2025-07-25 Mazharuddin Mehraban , Saeid Alikhani

Understanding which system structure can sustain stable dynamics is a fundamental step in the design and analysis of large scale dynamical systems. Towards this goal, we investigate here the structural stability of systems with a random…

Combinatorics · Mathematics 2020-03-26 Mohamed Ali Belabbas , Artur Kirkoryan

We prove a version of the strong Taylor's conjecture for stable graphs: if $G$ is a stable graph whose chromatic number is strictly greater than $\beth_2(\aleph_0)$ then $G$ contains all finite subgraphs of Sh$_n(\omega)$ and thus has…

Logic · Mathematics 2021-03-26 Yatir Halevi , Itay Kaplan , Saharon Shelah

A set D of vertices of a graph G=(V,E) is irredundant if each v of D satisfies (a) v is isolated in the subgraph induced by D, or (b) v is adjacent to a vertex in V-D that is nonadjacent to all other vertices in D. The upper irredundance…

Combinatorics · Mathematics 2021-04-08 Kieka Mynhardt , Riana Roux

A signed graph is a pair $(G,\Sigma)$, where $G=(V,E)$ is a graph (in which parallel edges are permitted, but loops are not) with $V={1,...,n}$ and $\Sigma\subseteq E$. By $S(G,\Sigma)$ we denote the set of all symmetric $V\times V$…

Combinatorics · Mathematics 2012-08-28 Marina Arav , Frank J. Hall , Zhongshan Li , Hein van der Holst

A graph $ G $ is said to be $ (H;k) $-vertex stable if $ G $ contains a~subgraph isomorphic to $ H $ even after removing any $ k $ of its vertices alongside with their incident edges. We will denote by $ \text{stab}(H;k) $ the minimum size…

Combinatorics · Mathematics 2021-06-16 Artur Kuźnar

Given two graphs G and H its 1-{\it join} is the graph obtained by taking the disjoint union of G and H and adding all the edges between a nonempty subset of vertices of G and a nonempty subset of vertices of H. In general, composition…

Combinatorics · Mathematics 2007-07-30 Carlos E. Valencia , Marcos I. Barrita

For an arbitrary invariant $\rho (G)$ of a graph $G$, the $\rho-$vertex stability number $vs_{\rho}(G)$ is the minimum number of vertices of $G$ whose removal results in a graph $H\subseteq G$ with $\rho (H)\neq \rho (G)$ or with…

Combinatorics · Mathematics 2020-04-23 Saeid Alikhani , Mohammad R. Piri

We determine the maximum number of edges of an $n$-vertex graph $G$ with the property that none of its $r$-cliques intersects a fixed set $M\subset V(G)$. For $(r-1)|M|\ge n$, the $(r-1)$-partite Turan graph turns out to be the unique…

Combinatorics · Mathematics 2017-07-31 Peter Allen , Julia Böttcher , Jan Hladký , Diana Piguet

A vertex subset $S$ of a graph $G$ is a general position set of $G$ if no vertex of $S$ lies on a geodesic between two other vertices of $S$. The cardinality of a largest general position set of $G$ is the general position number ${\rm…

Combinatorics · Mathematics 2019-04-17 Bijo S. Anand , Ullas Chandran S. V. , Manoj Changat , Sandi Klavžar , Elias John Thomas

In this paper, we study the stability result of a well-known theorem of Bondy. We prove that for any 2-connected non-hamiltonian graph, if every vertex except for at most one vertex has degree at least $k$, then it contains a cycle of…

Combinatorics · Mathematics 2025-10-17 Bo Ning , Long-tu Yuan

An instance of the super-stable matching problem with incomplete lists and ties is an undirected bipartite graph $G = (A \cup B, E)$, with an adjacency list being a linearly ordered list of ties. Ties are subsets of vertices equally good…

Discrete Mathematics · Computer Science 2021-05-21 Changyong Hu , Vijay K. Garg

The Erd\H{o}s-Simonovits stability theorem is one of the most widely used theorems in extremal graph theory. We obtain an Erd\H{o}s-Simonovits type stability theorem in multi-partite graphs. Different from the Erd\H{o}s-Simonovits stability…

Combinatorics · Mathematics 2026-01-14 Wanfang Chen , Changhong Lu , Long-Tu Yuan

A non-empty set $S\subseteq V (G)$ of the simple graph $G=(V(G),E(G))$ is an independent dominating set of $G$ if every vertex not in $S$ is adjacent with some vertex in $S$ and the vertices of $S$ are pairwise non-adjacent. The independent…

Combinatorics · Mathematics 2023-11-06 Saeid Alikhani , Mazharodin Mehraban , Alexei Zakharov , Hamidreza Golmohammadi