Let T2 be the graph obtained from the Petersen graph by first deleting a vertex and then contracting an edge incident to a vertex of degree two. We give a simple characterization of the graphs that contain no subdivision of T2. This characterization is used to show that if every planar r-graph is r-
Subdivisions and Chromatic Roots
β Scribed by Jason I. Brown
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 77 KB
- Volume
- 76
- Category
- Article
- ISSN
- 0095-8956
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