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Related papers: Two lower bounds for maximum matching

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The maximum matching width is a width-parameter that is defined on a branch-decomposition over the vertex set of a graph. The size of a maximum matching in the bipartite graph is used as a cut-function. In this paper, we characterize the…

Combinatorics · Mathematics 2016-06-24 Jisu Jeong , Seongmin Ok , Geewon Suh

A matching in a graph is uniquely restricted if no other matching covers exactly the same set of vertices. We establish tight lower bounds on the maximum size of a uniquely restricted matching in terms of order, size, and maximum degree.

Combinatorics · Mathematics 2018-04-30 M. Fürst , D. Rautenbach

Three well-studied types of subgraph-restricted matchings are induced matchings, uniquely restricted matchings, and acyclic matchings. While it is hard to determine the maximum size of a matching of each of these types, whether some given…

Combinatorics · Mathematics 2017-10-24 M. Fürst , D. Rautenbach

It is well-known that every maximal planar graph has a matching of size at least $\tfrac{n+8}{3}$ if $n\geq 14$. In this paper, we investigate similar matching-bounds for maximal \emph{1-planar} graphs, i.e., graphs that can be drawn such…

Combinatorics · Mathematics 2023-01-05 Therese Biedl , John Wittnebel

We prove that every connected cubic graph with $n$ vertices has a maximal matching of size at most $\frac{5}{12} n+ \frac{1}{2}$. This confirms the cubic case of a conjecture of Baste, F\"urst, Henning, Mohr and Rautenbach (2019) on regular…

Combinatorics · Mathematics 2021-08-10 Wouter Cames van Batenburg

We show that any $2-$factor of a cubic graph can be extended to a maximum $3-$edge-colorable subgraph. We also show that the sum of sizes of maximum $2-$ and $3-$edge-colorable subgraphs of a cubic graph is at least twice of its number of…

Discrete Mathematics · Computer Science 2014-05-01 Davit Aslanyan , Vahan V. Mkrtchyan , Samvel S. Petrosyan , Gagik N. Vardanyan

In this note we analyze two algorithms, one for producing a matching and one for an independent set, on $k$-uniform $d$-regular hypergraphs of large girth. As a result we obtain new lower bounds on the size of a maximum matching or…

Combinatorics · Mathematics 2023-07-31 Deepak Bal , Patrick Bennett

In recent years there has been increased interest in extremal problems for "counting" parameters of graphs. For example, the Kahn-Zhao theorem gives an upper bound on the number of independent sets in a $d$-regular graph. In the same…

Combinatorics · Mathematics 2013-10-08 L. Keough , A. J. Radcliffe

We give an upper bound on the number of perfect matchings in simple graphs with a given number of vertices and edges. We apply this result to give an upper bound on the number of 2-factors in a directed complete bipartite balanced graph on…

Combinatorics · Mathematics 2014-08-01 M. Aaghabali , S. Akbari , S. Friedland , K. Markstrom , Z. Tajfirouz

Perfect matchings and maximum weight matchings are two fundamental combinatorial structures. We consider the ratio between the maximum weight of a perfect matching and the maximum weight of a general matching. Motivated by the computer…

Discrete Mathematics · Computer Science 2018-11-08 Emilio Vital Brazil , Guilherme D. da Fonseca , Celina de Figueiredo , Diana Sasaki

For the set of graphs with a given degree sequence, consisting of any number of $2's$ and $1's$, and its subset of bipartite graphs, we characterize the optimal graphs who maximize and minimize the number of $m$-matchings. We find the…

Combinatorics · Mathematics 2008-01-16 S. Friedland , E. Krop , K. Markström

We study the minimum number of maximum matchings in a bipartite multigraph G with parts $X$ and $Y$ under various conditions, refining the well-known lower bound due to M. Hall. When $|X|=n$, every vertex in $X$ has degree at least $k$, and…

Combinatorics · Mathematics 2022-11-21 Alexandr V. Kostochka , Douglas B. West , Zimu Xiang

This article provides sharp bounds for the maximum number of edges possible in a simple graph with restricted values of two of the three parameters, namely, maxi- mum matching size, independence number and maximum degree. We also construct…

Combinatorics · Mathematics 2012-03-08 Niraj Khare , Nishali Mehta , Naushad Puliyambalath

For a graph G, consider the pairs of edge-disjoint matchings whose union consists of as many edges as possible. Let H be the largest matching among such pairs. Let M be a maximum matching of G. We show that 5/4 is a tight upper bound for…

Discrete Mathematics · Computer Science 2008-10-09 V. V. Mkrtchyan , V. L. Musoyan , A. V. Tserunyan

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

We give an upper bound on the number of perfect matchings in an undirected simple graph $G$ with an even number of vertices, in terms of the degrees of all the vertices in $G$. This bound is sharp if $G$ is a union of complete bipartite…

Combinatorics · Mathematics 2008-03-07 Shmuel Friedland

A matching is a set of edges without common endpoint. It was recently shown that every 1-planar graph (i.e., a graph that can be drawn in the plane with at most one crossing per edge) that has minimum degree 3 has a matching of size at…

Computational Geometry · Computer Science 2020-03-19 Therese Biedl , Fabian Klute

We give upper bounds for the number $\Phi_\ell(G)$ of matchings of size $\ell$ in (i) bipartite graphs $G=(X\cup Y, E)$ with specified degrees $d_x$ ($x\in X$), and (ii) general graphs $G=(V,E)$ with all degrees specified. In particular,…

Combinatorics · Mathematics 2012-05-22 Liviu Ilinca , Jeff Kahn

For bipartite graphs the NP-completeness is proved for the problem of existence of maximum matching which removal leads to a graph with given lower(upper)bound for the cardinality of its maximum matching.

Discrete Mathematics · Computer Science 2008-03-08 R. R. Kamalian , V. V. Mkrtchyan

A matching cut in a graph G is an edge cut of G that is also a matching. This short survey gives an overview of old and new results and open problems for Maximum Matching Cut, which is to determine the size of a largest matching cut in a…

Combinatorics · Mathematics 2023-12-21 Van Bang Le , Felicia Lucke , Daniël Paulusma , Bernard Ries
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