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DUALIZABILITY OF GRAPHS

Published online by Cambridge University Press:  24 February 2011

SARAH M. JOHANSEN*
Affiliation:
Department of Mathematics, La Trobe University, Victoria 3086, Australia (email: S.Johansen@latrobe.edu.au)
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Abstract

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We investigate natural dualities for classes of simple graphs. For example, we give a natural duality for the class consisting of all n-colourable graphs and show that, for all n≥3, there is no natural duality for the class consisting of all freely n-colourable graphs. We also prove that there exist arbitrarily long finite chains of 3-colourable graphs that alternate between being dualizable and nondualizable.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2011

References

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