In this paper w e determine the circumstances under which a set of 11 vertices in a 3-connected cubic graph lies on a cycle. In addition, w e consider the number of such cycles that exist and characterize those graphs in which a set of 9 vertices lies in exactly two cycles.
Vertex suppression in 3-connected graphs
✍ Scribed by Matthias Kriesell
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 265 KB
- Volume
- 57
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
To suppress a vertex $v$ in a finite graph G means to delete it and add an edge from a to b if a, b are distinct nonadjacent vertices which formed the neighborhood of $v$. Let $G--x$ be the graph obtained from $G-x$ by suppressing vertices of degree at most 2 as long as it is possible; this is proven to be well defined.
Our main result states that every 3‐connected graph G has a vertex x such that $G -- x$ is 3‐connected unless G is isomorphic to $K_{3,3}$, $K_2 \times K_3$, or to a wheel $K_{1}*C_{\ell}$ for some $\ell \geq 3$. This leads to a generator theorem for 3‐connected graphs in terms of series parallel extensions. © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 41–54, 2008
📜 SIMILAR VOLUMES
## Abstract The concept of a matroid vertex is introduced. The vertices of a matroid of a 3‐connected graph are in one‐to‐one correspondence with vertices of the graph. Thence directly follows Whitney's theorem that cyclic isomorphism of 3‐connected graphs implies isomorphism. The concept of a vert
## Abstract An edge __e__ of a 3‐connected graph __G__ is said to be __removable__ if __G__ ‐ __e__ is a subdivision of a 3‐connected graph. If __e__ is not removable, then __e__ is said to be __nonremovable.__ In this paper, we study the distribution of removable edges in 3‐connected graphs and pr
We prove that every 3-connected graph \(G\) of order at least nine has two adjacent edges \(x y\) and \(y z\) such that the graph obtained from \(G\) by contracting \(x, y\), and \(z\) into a single vertex is also 3-connected. (i) 1994 Academic Press. Inc.
Moon and Moser in 1963 conjectured that if G is a 3-connected planar graph on n vertices, then G contains a cycle of length at least Oðn log 3 2 Þ: In this paper, this conjecture is proved. In addition, the same result is proved for 3-connected graphs embeddable in the projective plane, or the torus