Forbidden subgraphs and the König-Egerváry property

The matching number of a graph is the maximum size of a set of vertex-disjoint edges. The transversal number is the minimum number of vertices needed to meet every edge. A graph has the König-Egerváry property if its matching number equals its transversal number. Lovász proved a characterization of...

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Detalles Bibliográficos
Autores: Bonomo, F., Dourado, M.C., Durán, G., Faria, L., Grippo, L.N., Safe, M.D.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:Argentina
Institución:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
Repositorio:Biblioteca Digital (UBA-FCEN)
Idioma:inglés
OAI Identifier:paperaa:paper_0166218X_v161_n16-17_p2380_Bonomo
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_0166218X_v161_n16-17_p2380_Bonomo
Access Level:acceso abierto
Palabra clave:Edge-perfect graphs
Forbidden subgraphs
König-Egerváry graphs
König-Egerváry property
Maximum matching
Forbidden configurations
Forbidden subgraph characterizations
Matching numbers
Maximum matchings
Perfect matchings
Transversal number
Characterization
Graphic methods
Graph theory
Descripción
Sumario:The matching number of a graph is the maximum size of a set of vertex-disjoint edges. The transversal number is the minimum number of vertices needed to meet every edge. A graph has the König-Egerváry property if its matching number equals its transversal number. Lovász proved a characterization of graphs having the König-Egerváry property by means of forbidden subgraphs within graphs with a perfect matching. Korach, Nguyen, and Peis proposed an extension of Lovász's result to a characterization of all graphs having the König-Egerváry property in terms of forbidden configurations (which are certain arrangements of a subgraph and a maximum matching). In this work, we prove a characterization of graphs having the König-Egerváry property by means of forbidden subgraphs which is a strengthened version of the characterization by Korach et al. Using our characterization of graphs with the König-Egerváry property, we also prove a forbidden subgraph characterization for the class of edge-perfect graphs. © 2013 Elsevier B.V. All rights reserved.