Very cost effective bipartitions in graphs

For a graph G=(V,E) and a set of vertices S⊆V, a vertex v∈S is said to be very cost effective if it is adjacent to more vertices in V∖S than in S. A bipartition π={S,V∖S} is called very cost effective if both S and V∖S are very cost effective sets. Not all graphs have a very cost effective bipartiti...

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Bibliographic Details
Main Authors: Teresa W. Haynes, Stephen T. Hedetniemi, Inna Vasylieva
Format: Article
Language:English
Published: Taylor & Francis Group 2015-11-01
Series:AKCE International Journal of Graphs and Combinatorics
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0972860015000365
Description
Summary:For a graph G=(V,E) and a set of vertices S⊆V, a vertex v∈S is said to be very cost effective if it is adjacent to more vertices in V∖S than in S. A bipartition π={S,V∖S} is called very cost effective if both S and V∖S are very cost effective sets. Not all graphs have a very cost effective bipartition, for example, the complete graphs of odd order do not. We characterize the cactus graphs having a very cost effective bipartition. Also, we show that if a graph G or H has a very cost effective bipartition, then so does the Cartesian product G□H.
ISSN:0972-8600