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A graph and its complement with specified properties V: The self-complement index

Published online by Cambridge University Press:  26 February 2010

Jin Akiyama
Affiliation:
University of Michigan, Department of Mathematics, Ann Arbor, M1 48109, U.S.A.
Geoffrey Exoo
Affiliation:
University of Michigan, Department of Mathematics, Ann Arbor, M1 48109, U.S.A.
Frank Harary
Affiliation:
University of Michigan, Department of Mathematics, Ann Arbor, M1 48109, U.S.A.
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Abstract

The self-complement index s(G) of a graph G is the maximum order of an induced subgraph of G whose complement is also induced in G. This new graphical invariant provides a measure of how close a given graph is to being selfcomplementary. We establish the existence of graphs G of order p having s(G) = n for all positive integers n < p. We determine s(G) for several families of graphs and find in particular that when G is a tree, s(G) = 4 unless G is a star for which s(G) = 2.

Type
Research Article
Copyright
Copyright © University College London 1980

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References

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