A graph is said to be projective-planar if it is nonplanar and is embeddable in a projective plane. In this paper we show that the numbers of projectiveplanar embeddings (up to equivalence) of all 5-connected graphs have an upper bound c( 1120).
Unique and faithful embeddings of projective-planar graphs
β Scribed by Seiya Negami
- Publisher
- John Wiley and Sons
- Year
- 1985
- Tongue
- English
- Weight
- 393 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
A graph G is uniquelyembeddable in a surface f 2 if for any two embeddings f,,f2 : G + f 2 , there exists an isomorphism u : G + G and a homeo-
admits an embedding f : G + F2 such that for any isomorphism (T : G + G, there is a homeomorphism h : F 2 f 2 with h . f = f . u. It will be shown that if a projective-planar graph G is 5-connected and contains a subdivision of the complete graph K6 as its subgraph, then G is uniquely embeddable in a projective plane, and that moreover if G is not isomorphic to K6, then G is faithfully embeddable in a projective plane.
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