Document Type : Research Paper

Authors

Department of Mathematics, Shahrood University of Technology, University Blvd., Shahrood, Iran

Abstract

An extended star is a tree which has only one vertex with degree larger than two. The -center problem in a graph  asks to find a subset  of the vertices of  of cardinality  such that the maximum weighted distances from  to all vertices is minimized. In this paper we consider the -center problem on the unweighted extended stars, and present some properties to find solution.

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