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Related papers: Graphs with Integer Matching Polynomial Roots

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In this note we present an infinite family of 2-connected graphs such that their matching polynomials have only integer zeros. This answers in negative a question of Akbari et al. [Graphs with integer matching polynomial zeros, Discrete…

Combinatorics · Mathematics 2021-09-14 Ebrahim Ghorbani

A matching covered graph $G$ is minimal if for each edge $e$ of $G$, $G-e$ is not matching covered. An edge $e$ of a matching covered graph $G$ is removable if $G-e$ is also matching covered. Thus a matching covered graph is minimal if and…

Combinatorics · Mathematics 2024-05-28 Yipei Zhang , Xiumei Wang , Jinjiang Yuan , C. T. Ng , T. C. E. Cheng

A graph is equimatchable if all of its maximal matchings have the same size. A graph is claw-free if it does not have a claw as an induced subgraph. In this paper, we provide, to the best of our knowledge, the first characterization of…

Discrete Mathematics · Computer Science 2018-07-26 Saieed Akbari , Hadi Alizadeh , Tınaz Ekim , Didem Gözüpek , Mordechai Shalom

We determine all graphs whose matching polynomials have at most five distinct zeros. As a consequence, we find new families of graphs which are determined by their matching polynomial.

Combinatorics · Mathematics 2012-04-24 Ebrahim Ghorbani

A graph is called equimatchable if all of its maximal matchings have the same size. Frendrup et al. [8] provided a characterization of equimatchable graphs with girth at least $5$. In this paper, we extend this result by providing a…

Discrete Mathematics · Computer Science 2021-08-31 Yasemin Büyükçolak , Didem Gözüpek , Sibel Özkan

The Induced Graph Matching problem asks to find k disjoint induced subgraphs isomorphic to a given graph H in a given graph G such that there are no edges between vertices of different subgraphs. This problem generalizes the classical…

Discrete Mathematics · Computer Science 2014-02-11 Danny Hermelin , Matthias Mnich , Erik Jan van Leeuwen

We show that deciding whether a given graph $G$ of size $m$ has a unique perfect matching as well as finding that matching, if it exists, can be done in time $O(m)$ if $G$ is either a cograph, or a split graph, or an interval graph, or…

Combinatorics · Mathematics 2017-12-13 S. Chaplick , M. Fürst , F. Maffray , D. Rautenbach

We present an algebraic characterization of perfect graphs, i.e., graphs for which the clique number and the chromatic number coincide for every induced subgraph. We show that a graph is perfect if and only if certain nonnegative…

Optimization and Control · Mathematics 2023-05-03 Amir Ali Ahmadi , Cemil Dibek

We call a finite undirected graph minimally k-matchable if it has at least k distinct perfect matchings but deleting any edge results in a graph which has not. An odd subdivision of some graph G is any graph obtained by replacing every edge…

Combinatorics · Mathematics 2016-08-05 Gasper Fijavz , Matthias Kriesell

A graph is called equimatchable if all of its maximal matchings have the same size. Due to Eiben and Kotrb\v{c}\'{i}k,, any connected graph with odd order and independence number $\alpha(G)$ at most $2$ is equimatchable. Akbari et al.…

Combinatorics · Mathematics 2025-09-15 Xiao Zhao , Haojie Zheng , Fengming Dong , Hengzhe Li , Yingbin Ma

Assume that there is a free group action of automorphisms on a bipartite graph. If there is a perfect matching on the factor graph, then obviously there is a perfect matching on the graph. Surprisingly, the reversed is also true for…

Group Theory · Mathematics 2016-07-26 Jan Fricke

A matching set $M$ in a graph $G$ is a collection of edges of $G$ such that no two edges from $M$ share a vertex. In this paper we consider some parameters related to the matching of regular graphs. We find the sixth coefficient of the…

Combinatorics · Mathematics 2017-10-23 Neda Soltani , Saeid Alikhani

We show if the flow polynomial of a bridgeless graph G has only integral roots, then G is the dual graph to a planar chordal graph. We also show that for 3-connected cubic graphs, the same conclusion holds under the weaker hypothesis that…

Combinatorics · Mathematics 2009-09-11 Joseph P. S. Kung , Gordon F. Royle

In this paper we investigate invertibility of graphs with a unique perfect matching, i.e. graphs having a unique 1-factor. We recall the new notion of the so-called negatively invertible graphs investigated by the authors in the recent…

Combinatorics · Mathematics 2016-12-08 Sona Pavlikova , Daniel Sevcovic

A graph is strongly perfect if every induced subgraph H has a stable set that meets every maximal clique of H. A graph is claw-free if no vertex has three pairwise non-adjacent neighbors. The characterization of claw-free graphs that are…

Combinatorics · Mathematics 2020-11-10 Maria Chudnovsky , Cemil Dibek

Testing whether there is an induced path in a graph spanning k given vertices is already NP-complete in general graphs when k=3. We show how to solve this problem in polynomial time on claw-free graphs, when k is not part of the input but…

Discrete Mathematics · Computer Science 2016-12-15 Jiri Fiala , Marcin Kaminski , Bernard Lidicky , Daniel Paulusma

For a connected graph $G=(V,E)$, a matching $M\subseteq E$ is a matching cut of $G$ if $G-M$ is disconnected. It is known that for an integer $d$, the corresponding decision problem Matching Cut is polynomial-time solvable for graphs of…

Combinatorics · Mathematics 2022-07-18 Felicia Lucke , Daniël Paulusma , Bernard Ries

A complete subgraph of a given graph is called a clique. A clique Polynomial of a graph is a generating function of the number of cliques in $G$. A real root of the clique polynomial of a graph $G$ is called a \emph{clique root} of $G$. \\…

Combinatorics · Mathematics 2021-12-21 Hossein Teimoori Faal

Given an undirected graph, are there $k$ matchings whose union covers all of its nodes, that is, a matching-$k$-cover? A first, easy polynomial solution from matroid union is possible, as already observed by Wang, Song and Yuan…

Combinatorics · Mathematics 2021-02-05 Dehia Ait Ferhat , Zoltán Király , András Sebő , Gautier Stauffer

A graph is called matching covered if for its every edge there is a maximum matching containing it. It is shown that minimal matching covered graphs contain a perfect matching.

Discrete Mathematics · Computer Science 2007-07-16 V. V. Mkrtchyan
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