On eccentric vertices in graphs
β Scribed by Chartrand, Gary; Schultz, Michelle; Winters, Steven J.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 387 KB
- Volume
- 28
- Category
- Article
- ISSN
- 0028-3045
No coin nor oath required. For personal study only.
β¦ Synopsis
The eccentricity e(u) of a vertex u in a connected graph G is the distance between u and a vertex furthest from u. The minimum eccentricity among the vertices of G is the radius rad G of G, and the maximum
The radial number m(u) of u is the minimum eccentricity among the eccentric vertices of u, while the diametrical number dn(u) of u is the maximum eccentricity among the eccentric vertices of u. The radial number m(G) of G is the minimum radial number among the vertices of G and the diametrical number dn(G) of G is the minimum diametrical number among the vertices of G. Several results concerning eccentric vertices are presented. It is shown that for positive integers a and b with a 5 b 5 2a there exists a connected graph G having rn(G) = a and dn(G) = b. Also, if a, b , and c are positive integers with a s b s c s 2a, then there exists a connected graph G with rad G = a, m(G) = b , and diam G = c.
π SIMILAR VOLUMES
For a vertex v and a (k Οͺ 1)-element subset P of vertices of a graph, one can define the distance from v to P in various ways, including the minimum, average, and maximum distance from v to P. Associated with each of these distances, one can define the k-eccentricity of the vertex v as the maximum d
Let G be a uniquely hamiltonian graph on n vertices. We show that G has a vertex of degree at most c log 2 8n+3, where c=(2&log 2 3) &1 r2.41. We show further that G has at least two vertices of degree less than four if it is planar and at least four vertices of degree two if it is bipartite.
## Abstract A necessary and sufficient condition is obtained for a set of 12 vertices in any 3βconnected cubic graph to lie on a common cycle.
## Abstract In this article, we prove the following theorem. Let __k__ββ₯β3 be an integer, __G__ be a __k__βconnected graph with minimum degree __d__ and __X__ be a set of __k__β+β1 vertices on a cycle. Then __G__ has a cycle of length at least min {2d,|V(G)|} passing through __X__. This result give