We prove that every planar 3-connected graph has a 2-connected spanning subgraph of maximum valence 15 . We give an example of a planar 3 -connected graph with no spanning 2-connected subgraph of maximum valence five. i) 1994 Academic Press, Inc.
2-connected 7-coverings of 3-connected graphs on surfaces
β Scribed by Ken-ichi Kawarabayashi; Atsuhiro Nakamoto; Katsuhiro Ota
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 116 KB
- Volume
- 43
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
An mβcovering of a graph G is a spanning subgraph of G with maximum degree at most m. In this paper, we shall show that every 3βconnected graph on a surface with Euler genus kββ₯β2 with sufficiently large representativity has a 2βconnected 7βcovering with at most 6__k__βββ12 vertices of degree 7. We also construct, for every surface F^2^ with Euler genus kββ₯β2, a 3βconnected graph G on F^2^ with arbitrarily large representativity each of whose 2βconnected 7βcoverings contains at least 6__k__βββ12 vertices of degree 7. Β© 2003 Wiley Periodicals, Inc. J Graph Theory 43: 26β36, 2003
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