ArticleOriginal scientific text

Title

The periphery graph of a median graph

Authors 1, 2, 2, 3

Affiliations

  1. Faculty of Natural Sciences and Mathematics, University of Maribor, Slovenia
  2. Department of Futures Studies, University of Kerala, Trivandrum-695034, India
  3. Faculty of Electrical Engineering and Computer Science, University of Maribor, Slovenia

Abstract

The periphery graph of a median graph is the intersection graph of its peripheral subgraphs. We show that every graph without a universal vertex can be realized as the periphery graph of a median graph. We characterize those median graphs whose periphery graph is the join of two graphs and show that they are precisely Cartesian products of median graphs. Path-like median graphs are introduced as the graphs whose periphery graph has independence number 2, and it is proved that there are path-like median graphs with arbitrarily large geodetic number. Peripheral expansion with respect to periphery graph is also considered, and connections with the concept of crossing graph are established.

Keywords

median graph, Cartesian product, geodesic, periphery, peripheral expansion

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Pages:
17-32
Main language of publication
English
Received
2008-06-11
Accepted
2009-01-05
Published
2010
Exact and natural sciences