The Strong Perfect Graph Conjecture states that a graph is perfect iff neither it nor its complement contains an odd chordless cycle of size greater than or equal to 5. In this article it is shown that many families of graphs are complete for this conjecture in the sense that the conjecture is true
On the strong perfect graph conjecture
β Scribed by Stephan Olariu
- Publisher
- John Wiley and Sons
- Year
- 1988
- Tongue
- English
- Weight
- 384 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
A graph G is perfect if for every induced subgraph H of G the chromatic number x(H) equals the largest number w ( H ) of pairwise adjacent vertices in H. Berge's famous Strong Perfect Graph Conjecture asserts that a graph G is perfect if and only if neither G nor its complement C contains an odd chordless cycle of length at least 5. Its resolution has eluded researchers for more than 20 years. We prove that the conjecture is true for a class of graphs that we describe by forbidden configurations.
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