The total chromatic number of an arbitrary graph is the smallest number of colours needed to colour the edges and vertices of the graph so that no two adjacent or incident elements of the graph receive the same colour. In this paper we prove that the problem of determining the total chromatic number
Determining the total colouring number is np-hard
✍ Scribed by Abdón Sánchez-Arroyo
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- English
- Weight
- 279 KB
- Volume
- 78
- Category
- Article
- ISSN
- 0012-365X
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✦ Synopsis
In this paper it is proved that the problem of deteruzining the totai chromatic number of an arbitrary'graph is NP-hard. The problem remains NP-hard even for cubic bipartite graphs.
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