Abbott, H.L. and B. Zhou, On a conjecture of Gallai concerning complete subgraphs of k-critical graphs, Discrete Mathematics 100 (1992) 223-228. A graph G is said to be k-critical if it has chromatic number k but every proper subgraph of G has a (k -l)-coloring. T. Gallai asked whether each k-criti
Proof of a conjecture of Dirac concerning 4-critical planar graphs
β Scribed by H.L. Abbott; M. Katchalski; B. Zhou
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 214 KB
- Volume
- 132
- Category
- Article
- ISSN
- 0012-365X
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