Vertex colorings with a distance restriction
✍ Scribed by Guantao Chen; András Gyárfás; R.H. Schelp
- Book ID
- 104114127
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 787 KB
- Volume
- 191
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
Let d, k be any two positive integers with k > d > 0. We consider a k-coloring of a graph G such that the distance between each pair of vertices in the same color-class is at least d. Such graphs are said to be (k,d)-colorable. The object of this paper is to determine the maximum size of (k, 3)-colorable, (k, 4)-colorable, and (k, k-1 )-colorable graphs. Sharp results are obtained for both (k, 3)-colorable and (k, k-1 )-colorable graphs, while the results obtained for (k, 4)-colorable graphs are close to the truth.
📜 SIMILAR VOLUMES
An edge-coloring is called vertex-distinguishing if every two distinct vertices are incident to different sets of colored edges. The minimum number of colors required for a vertex-distinguishing proper edge-coloring of a simple graph G is denoted by χ s (G). A simple count shows that χ s (G) ≥ max{(
Lawrence [2, Theorem 3] and Borodin and Kostochka [1, Lemma 2' 1 both give the same theorem about vertex colorings of graphs (Corollary 1 below). But Lawrence's proof, although powerful, is a little long, and Borodin and Kostoehka state the result without a proof.