A covering projection from a graph G onto a graph H is a ``local isomorphism'': a mapping from the vertex set of G onto the vertex set of H such that, for every v # V(G), the neighborhood of v is mapped bijectively onto the neighborhood (in H ) of the image of v. We investigate two concepts that con
Reorientations of covering graphs
✍ Scribed by Graham Brightwell; Jaroslav Nešetřil
- Publisher
- Elsevier Science
- Year
- 1991
- Tongue
- English
- Weight
- 252 KB
- Volume
- 88
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
The aim of this paper is to construct a graph G on n vertices which is a connected covering graph but has 2O(") diagram orientations.
This provides a negative answer to a question of I. Rival.
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