DMGT

ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

https://doi.org/10.7151/dmgt

Discussiones Mathematicae Graph Theory

Journal Impact Factor (JIF 2022): 0.7

5-year Journal Impact Factor (2022): 0.7

CiteScore (2022): 1.9

SNIP (2022): 0.902

Discussiones Mathematicae Graph Theory

Article in volume


Authors:

Y. Büyükçolak

Yasemin Büyükçolak

Department of Mathematics, Gebze Technical University

email: turediyasemin@gmail.com

D. Gözüpek

Didem Gözüpek

Department of Computer Engineering, Gebze Technical University

email: didem.gozupek@gtu.edu.tr

S. Özkan

Title:

Equimatchable bipartite graphs

PDF

Source:

Discussiones Mathematicae Graph Theory 43(1) (2023) 77-94

Received: 2020-02-09 , Revised: 2020-07-21 , Accepted: 2020-07-21 , Available online: 2020-09-12 , https://doi.org/10.7151/dmgt.2356

Abstract:

A graph is called equimatchable if all of its maximal matchings have the same size. Lesk et al. [Equi-matchable graphs, Graph Theory and Combinatorics (Academic Press, London, 1984) 239–254] has provided a characterization of equimatchable bipartite graphs. Motivated by the fact that this characterization is not structural, Frendrup et al. [A note on equimatchable graphs, Australas. J. Combin. 46 (2010) 185–190] has also provided a structural characterization for equimatchable graphs with girth at least five, in particular, a characterization for equimatchable bipartite graphs with girth at least six. In this paper, we extend the characterization of Frendrup by eliminating the girth condition. For an equimatchable graph, an edge is said to be a critical-edge if the graph obtained by the removal of this edge is not equimatchable. An equimatchable graph is called edge-critical, denoted by ECE, if every edge is critical. Noting that each ECE-graph can be obtained from some equimatchable graph by recursively removing non-critical edges, each equimatchable graph can also be constructed from some ECE-graph by joining some non-adjacent vertices. Our study reduces the characterization of equimatchable bipartite graphs to the characterization of bipartite ECE-graphs.

Keywords:

equimatchable, edge-critical, bipartite graphs

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