ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory 18(1) (1998) 73-84
DOI: 10.7151/dmgt.1064


Halina Bielak

Institute of Mathematics
M. Curie-Skłodowska University



In this paper, the chromaticity of K3-gluings of two wheels is studied. For each even integer n ≥ 6 and each odd integer 3 ≤ q ≤ [n/2] all K3-gluings of wheels Wq+2 and Wn-q+2 create an χ-equivalent class.

Keywords: chromatically equivalent graphs, chromatic polynomial, chromatically unique graphs, wheels.

1991 Mathematics Subject Classification: 05C15.


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Received 18 April 1997
Revised 28 August 1997