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Related papers: Two lower bounds for maximum matching

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We study the maximal rank in affine subspaces of symmetric or alternating matrices, in terms of the matching numbers of certain associated graphs. Applications include simple proofs of upper bounds on the dimension of such subspaces in…

Combinatorics · Mathematics 2017-03-17 Roy Meshulam

A conjecture of the first two authors is that $n$ matchings of size $n$ in any graph have a rainbow matching of size $n-1$. We prove a lower bound of $\frac{2}{3}n-1$, improving on the trivial $\frac{1}{2}n$, and an analogous result for…

Combinatorics · Mathematics 2021-10-08 Ron Aharoni , Eli Berger , Maria Chudnovsky , Shira Zerbib

We give a sharp lower bound on the number of matchings of a given size in a bipartite graph. When specialized to regular bipartite graphs, our results imply Friedland's Lower Matching Conjecture and Schrijver's theorem proven by Gurvits and…

Combinatorics · Mathematics 2015-11-06 Marc Lelarge

A graph is said to be equimatchable if all its maximal matchings are of the same size. In this work we introduce two extensions of the property of equimatchability by defining two new graph parameters that measure how far a graph is from…

Combinatorics · Mathematics 2016-12-28 Zakir Deniz , Tınaz Ekim , Tatiana Romina Hartinger , Martin Milanič , Mordechai Shalom

We introduce a `concrete complexity' model for studying algorithms for matching in bipartite graphs. The model is based on the "demand query" model used for combinatorial auctions. Most (but not all) known algorithms for bipartite matching…

Computational Complexity · Computer Science 2019-06-12 Noam Nisan

The maximum matching problem on random graphs is studied analytically by the cavity method of statistical physics. When the average vertex degree \mth{c} is larger than \mth{2.7183}, groups of max-matching patterns which differ greatly from…

Disordered Systems and Neural Networks · Physics 2007-05-23 Haijun Zhou , Zhong-can Ou-Yang

The acyclic matching number of a graph $G$ is the largest size of an acyclic matching in $G$, that is, a matching $M$ in $G$ such that the subgraph of $G$ induced by the vertices incident to an edge in $M$ is a forest. We show that the…

Combinatorics · Mathematics 2017-10-30 M. Fürst , D. Rautenbach

It was conjectured by Mkrtchyan, Petrosyan, and Vardanyan that every graph $G$ with $\Delta(G)-\delta(G) \le 1$ has a maximum matching $M$ such that any two $M$-unsaturated vertices do not share a neighbor. In this note, we confirm the…

Combinatorics · Mathematics 2016-11-22 Dong Ye

Finding a maximum-cardinality or maximum-weight matching in (edge-weighted) undirected graphs is among the most prominent problems of algorithmic graph theory. For $n$-vertex and $m$-edge graphs, the best known algorithms run in…

Data Structures and Algorithms · Computer Science 2021-05-10 Tomohiro Koana , Viatcheslav Korenwein , André Nichterlein , Rolf Niedermeier , Philipp Zschoche

While there have been many results on lower bounds for Max Cut in unweighted graphs, there are only few results for lower bounds for Max Cut in weighted graphs. In this paper, we launch an extensive study of lower bounds for Max Cut in…

Combinatorics · Mathematics 2024-08-13 Gregory Gutin , Anders Yeo

We prove a lower bound on the space complexity of two-pass semi-streaming algorithms that approximate the maximum matching problem. The lower bound is parameterized by the density of Ruzsa-Szemeredi graphs: * Any two-pass semi-streaming…

Data Structures and Algorithms · Computer Science 2021-08-17 Sepehr Assadi

In 1979, Nishizeki and Baybars showed that every planar graph with minimum degree 3 has a matching of size $\frac{n}{3}+c$ (where the constant $c$ depends on the connectivity), and even better bounds hold for planar graphs with minimum…

Discrete Mathematics · Computer Science 2020-02-21 Therese Biedl , John Wittnebel

$\Theta_6$-Graphs graphs are important geometric graphs that have many applications especially in wireless sensor networks. They are equivalent to Delaunay graphs where empty equilateral triangles take the place of empty circles. We…

Computational Geometry · Computer Science 2019-03-13 Therese Biedl , Ahmad Biniaz , Veronika Irvine , Kshitij Jain , Philipp Kindermann , Anna Lubiw

Bidirected graphs are a generalisation of directed graphs that arises in the study of undirected graphs with perfect matchings. Menger's famous theorem - the minimum size of a set separating two vertex sets $X$ and $Y$ is the same as the…

Combinatorics · Mathematics 2023-06-29 Nathan Bowler , Ebrahim Ghorbani , Florian Gut , Raphael W. Jacobs , Florian Reich

This paper considers pairs of optimization problems that are defined from a single input and for which it is desired to find a good approximation to either one of the problems. In many instances, it is possible to efficiently find an…

Data Structures and Algorithms · Computer Science 2009-09-11 David Eppstein

A bisection of a graph is a bipartition of its vertex set such that the two resulting parts differ in size by at most 1, and its size is the number of edges that connect vertices in the two parts. The perfect matching condition and…

Combinatorics · Mathematics 2024-11-19 Jianfeng Hou , Shufei Wu , Yuanyuan Zhong

The fractional matching number of a graph G, is the maximum size of a fractional matching of G. The following sharp lower bounds for a graph G of order n are proved, and all extremal graphs are characterized in this paper. (1)The sum of the…

Combinatorics · Mathematics 2021-05-31 Ting Yang , Xiying Yuan

An induced matching in a graph is a set of edges whose endpoints induce a $1$-regular subgraph. Gupta et al. (2012,\cite{Gupta}) showed that every $n$-vertex graph has at most $10^{\frac{n}{5}}\approx 1.5849^n$ maximal induced matchings,…

Combinatorics · Mathematics 2024-10-16 Bo-Jun Yuan , Zhao-Yu Yang , Lu Zheng , Shi-Cai Gong

A matching in a graph is uniquely restricted if no other matching covers exactly the same set of vertices. This notion was defined by Golumbic, Hirst, and Lewenstein and studied in a number of articles. Our contribution is twofold. We…

Combinatorics · Mathematics 2016-11-22 Julien Baste , Dieter Rautenbach , Ignasi Sau

We use probabilistic methods to find lower bounds on the maximum number, in a graph with domination number \gamma, of dominating sets of size \gamma. We find that we can randomly generate a graph that, w.h.p., is dominated by almost all…

Combinatorics · Mathematics 2013-08-15 Samuel Connolly , Zachary Gabor , Anant Godbole , Bill Kay