The kdomination number of a graph G, y k ( G ) , is the least cardinality of a set U of verticies such that any other vertex is adjacent to at least k vertices of U. We prove that if each vertex has degree at least k. then YAG) 5 kp/(k + 1).
An upper bound for orders of certain (k, k))-connected graphs
β Scribed by Kiyoshi Ando
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 275 KB
- Volume
- 135
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
A fragment of a connected graph G is a subset A of V(C) consisting of components of G-S such that V(G)-S-A #0 where S is a minimum cut of G. A graph G is said to be (k, I;)-
We prove the following result. Let k and k be integers with 1 <i < k, and let G be a critically (k, k)-connected graph. If no minimum cut of G (resp. G) contains all the elemental fragments of c (resp. G), then Moreover, for any given positive integers k and k, there is a critically (k, k)-connected graph for which the above equality holds.
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