An upper bound for the radius of a 3-connected graph
β Scribed by Jochen Harant
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 286 KB
- Volume
- 122
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
For a 3-connected graph with radius r containing n vertices, in [1] r < n/4 + O(log n) was proved and r < n/4 + const was conjectured.
Here we prove r < n/4 + 8.
Let G be a simple 3-connected finite graph on n vertices with vertex set V(G) and edge set E(G). For X, YE V(G) we denote by d(X, Y) the distance between X and Y. A vertex ZE V(G) is called a central vertex of G if max d(Z, Y)= min max d(X, Y).
YEV(G) XEV(G) YEV(G)
π SIMILAR VOLUMES
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
## Abstract The cyclic chromatic number of a plane graph __G__ is the smallest number Ο~__c__~(__G__) of colors that can be assigned to vertices of __G__ in such a way that whenever two distinct vertices are incident with a common face, they receive distinct colors. It was conjectured by Plummer an
## Abstract The path number of a graph __G__, denoted __p(G)__, is the minimum number of edgeβdisjoint paths covering the edges of __G.__ LovΓ‘sz has proved that if __G__ has __u__ odd vertices and __g__ even vertices, then __p(G)__ β€ 1/2 __u__ + __g__ β 1 β€ __n__ β 1, where __n__ is the total numbe
An upper bound for the harmonious chromatic number of a graph G is given. Three corollaries of the theorem are theorems or improvements of the theorems of Miller and Pritikin. The assignment of colors to the vertices of a graph such that each vertex has exactly one color has been studied for well o
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).