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Proyecciones (Antofagasta)

Print version ISSN 0716-0917

Proyecciones (Antofagasta) vol.37 no.2 Antofagasta June 2018

http://dx.doi.org/10.4067/S0716-09172018000200239 

Articles

A new family of chromatically unique 6-bridge graph

N. S. A. Karim1 

R. Hasni2 

1 Universiti Pendidikan Sultan Idris, Faculty of Science and Mathematics, Department of Mathematics, 35900 Tanjong Malim, Perak, Malaysia. E-mail: yaya_kulaan@yahoo.com

2 University Malaysia Terengganu, School of Informatics and Applied Mathematics, 21030 Kuala Terengganu, Terengganu, Malaysia. E-mail: hroslan@umt.edu.my

Abstract:

For a graph G, let P(G,λ) denote the chromatic polynomial of G. Two graphs G and H are chromatically equivalent (or simply χ-equivalent), denoted by G∼ H, if P(G,λ)=P(H,λ). A graph G is chromatically unique (or simply χ-unique) if for any graph H such as H∼ G, we have H≅ G, i.e, H is isomorphic to G. In this paper, the chromatic uniqueness of a new family of 6-bridge graph θ (a,a,b,b,b,c) where 2≤ a≤ b≤ c, is investigated.

Keywords : Chromatic polynomial; Chromatically unique; 6-bridge graph.

2000 Mathematical Subject Classification : Primary 05C15.

Texto completo disponible sólo en PDF.

Full text available only in PDF format.

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Received: May 2017; Accepted: January 2018

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