Colorings of disk graphs arise in the study of the frequency-assignment problem in broadcast networks. Motivated by the observations that the chromatic number of graphs modeling real networks hardly exceeds their clique number, we examine the related properties of the unit disk (UD) graphs and their
On the cost-chromatic number of graphs
β Scribed by John Mitchem; Patrick Morriss
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 566 KB
- Volume
- 171
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
We consider vertex colorings in which each color has an associated cost, incurred each time the color is assigned to a vertex. For a given set of costs, a minimum-cost coloring is a vertex coloring which makes the total cost of coloring the graph as small as possible. The cost-chromatic number of a graph with respect to a cost set is the minimum number of colors necessary to produce a minimum-cost coloring of the graph.
We establish upper bounds on the cost-chromatic number, show that trees and planar blocks can have arbitrarily large cost-chromatic number, and show that cost-chromatic number is not monotonic with subgraph inclusion.
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