## Abstract This paper proves that every (__n__β+β)βchromatic graph contains a subgraph __H__ with $\chi \_c (H) = n$. This provides an easy method for constructing sparse graphs __G__ with $\chi\_c (G) = \chi ( G) = n$. It is also proved that for any Ξ΅β>β0, for any fraction __k/d__β>β2, there exis
Chromatic numbers of subgraphs
β Scribed by F. Galvin
- Publisher
- Springer Netherlands
- Year
- 1973
- Tongue
- English
- Weight
- 124 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0031-5303
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