Alliance free sets in Cartesian product graphs

  • Authors:
  • Ismael G. Yero;Juan A. RodríGuez-VeláZquez;Sergio Bermudo

  • Affiliations:
  • Departamento de Matemáticas, Escuela Politécnica Superior de Algeciras, Universidad de Cádiz, Av. Ramón Puyol s/n, 11202 Algeciras, Spain;Departament d'Enginyeria Informítica i Matemítiques, Universitat Rovira i Virgili, Av. Països Catalans 26, 43007 Tarragona, Spain;Department of Economy, Quantitative Methods and Economic History, Pablo de Olavide University, Carretera de Utrera Km. 1, 41013-Sevilla, Spain

  • Venue:
  • Discrete Applied Mathematics
  • Year:
  • 2013

Quantified Score

Hi-index 0.04

Visualization

Abstract

Let G=(V,E) be a graph. For a non-empty subset of vertices S@?V, and vertex v@?V, let @d"S(v)=|{u@?S:uv@?E}| denote the cardinality of the set of neighbors of v in S, and let S@?=V-S. Consider the following condition: (1)@d"S(v)=@d"S"@?(v)+k, which states that a vertex v has at least k more neighbors in S than it has in S@?. A set S@?V that satisfies Condition (1) for every vertex v@?S is called a defensivek-alliance and for every vertex v in the open neighborhood of S is called an offensivek-alliance. A subset of vertices S@?V is a powerfulk-alliance if it is both a defensive k-alliance and an offensive (k+2)-alliance. Moreover, a subset X@?V is a defensive (an offensive or a powerful) k-alliance free set if X does not contain any defensive (offensive or powerful, respectively) k-alliance. In this article we study the relationships between defensive (offensive, powerful) k-alliance free sets in Cartesian product graphs and defensive (offensive, powerful) k-alliance free sets in the factor graphs.