In this paper, we shall first prove that for a Halin graph G, 4 Β°xT (G) Β°6, where x T (G) is the vertex-face total chromatic number of G. Second, we shall establish a sufficient condition for a Halin graph to have a vertex-face total chromatic number of 6. Finally, we shall give a necessary and suff
On the vertex face total chromatic number of planar graphs
β Scribed by Weifan, Wang; Jiazhuang, Liu
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 471 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Let G be a planar graph. The vertex face total chromatic number ,y13(G) of G is the least number of colors assigned to V(G) U F(G) such that no adjacent or incident elements receive the same color. The main results of this paper are as follows: (1) We give the vertex face total chromatic number for all outerplanar graphs and modulus 3-regular maximal planar graphs. (2) We prove that if G is a maximal planar graph or a lower degree planar graph, i.e., A(G) 5 3, then ,y13(G) 5 6. 0 1996 John Wiley & Sons, Inc.
Definition 1.1. A proper vertex face total coloring of a planar graph G, which is called a VFcoloring of G in short, is an assignment of colors to SvF(G) such that no adjacent or incident elements receive the same color. If G has a proper VF-coloring using k colors then G is called
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