A vertex coloring c : V β {1, 2, . . . , t} of a graph G = (V , E) is a vertex t-ranking if for any two vertices of the same color every path between them contains a vertex of larger color. The vertex ranking number Ο r (G) is the smallest value of t such that G has a vertex t-ranking. A Ο r (G)-ran
The rank of a graph after vertex addition
β Scribed by Jean H. Bevis; Kevin K. Blount; George J. Davis; Gayla S. Domke; Valerie A. Miller
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 471 KB
- Volume
- 265
- Category
- Article
- ISSN
- 0024-3795
No coin nor oath required. For personal study only.
β¦ Synopsis
Let r(G) denote the rank of the adjacency matrix of a graph G. When a vertex and its incident edges are deleted from G, the rank of the resultant graph cannot exceed r(G) and can decrease by at most 2. The problem of determining the exact effect of adding a single vertex to a graph is more difficult, since the number of edges that can be added with this vertex is variable. The rank of the new graph cannot decrease and it can increase by at most 2. We obtain results examining several cases of vertex addition.
π SIMILAR VOLUMES
A d-regular graph is said to be superconnected if any disconnecting subset with cardinality at most d is formed by the neighbors of some vertex. A superconnected graph that remains connected after the failure of a vertex and its neighbors will be called vosperian. Let be a vertex-transitive graph of
Wiseman, J.A., On the intersection rank of a graph, Discrete Mathematics 104 293-305.
## Abstract We prove in this note that the linear vertexβarboricity of any planar graph is at most three, which confirms a conjecture due to Broere and Mynhardt, and others.