Ond-diagonal colorings
β Scribed by Sanders, Daniel P.; Zhao, Yue
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 599 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
A coloring of a graph embedded on a surface is d-diagonal if any pair of vertices that are in the same face after the deletion of a t most d edges of the graph must be colored differently. Hornak and Jendrol introduced d-diagonal colorings as a generalization of cyclic colorings and diagonal colorings. This paper proves a conjecture of Hornak and Jendrol that plane quadrangulations have d-diagonal colorings with at most 1 + 2 . colors. A similar result is proven for plane triangulations. Each of these results extends to the projective plane. Also, a lower bound for the d-diagonal chromatic number is given.
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