We develop a connection between vertex coloring in graphs and star arboricity which allows us to prove that every planar graph has star arboricity at most 5. This settles an open problem raised independently by Algor and Alon and by Ringel. We also show that deciding if a graph has star arboricity 2
On incidence coloring and star arboricity of graphs
β Scribed by Barry Guiduli
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 190 KB
- Volume
- 163
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
In this note we show that the concept of incidence coloring introduced by Brualdi and Massey [4] is a special case of directed star arboricity, introduced by Agor and Alon ['2]. A conjecture in [4] concerning asymptotics of the incidence coloring number is solved in the negative following an example in [2]. We generalize a result in [3] concerning the star arboricity of graphs to the directed case by a slight modification of their proof, to give the same asymptotic bound as in the undirected case. As a result, we get tight asymptotic bounds for the maximum incidence coloring number of a graph in terms of its degree.
π SIMILAR VOLUMES
## Abstract A __star coloring__ of an undirected graph __G__ is a proper vertex coloring of __G__ (i.e., no two neighbors are assigned the same color) such that any path of length 3 in __G__ is not bicolored. The __star chromatic number__ of an undirected graph __G__, denoted by Ο~s~(__G__), is the
## Abstract A proper coloring of the vertices of a graph is called a __star coloring__ if the union of every two color classes induces a star forest. The star chromatic number Ο~__s__~(__G__) is the smallest number of colors required to obtain a star coloring of __G__. In this paper, we study the r
## Abstract A __star coloring__ of a graph is a proper vertexβcoloring such that no path on four vertices is 2βcolored. We prove that the vertices of every bipartite planar graph can be star colored from lists of size 14, and we give an example of a bipartite planar graph that requires at least eig
A subgraph H of a graph G is called a star-subgraph if each component of H is a star. The star-arboricify of G, denoted by sa(G), is the minimum number of star-subgraphs that partition the edges of G. In this paper we show that sa(G) is [r/21 + 1 or [r/2] + 2 for the complete r-regular multipartite