This article is motivated by a conjecture of Thomassen and Toft on the number s 2 (G) of separating vertex sets of cardinality 2 and the number v 2 (G) of vertices of degree 2 in a graph G belonging to the class G of all 2-connected graphs without nonseparating induced cycles. Let G denote the numbe
On a conjecture of Thomassen concerning subgraphs of large girth
✍ Scribed by Domingos Dellamonica Jr; Václav Koubek; Daniel M. Martin; Vojtěch Rödl
- Publisher
- John Wiley and Sons
- Year
- 2010
- Tongue
- English
- Weight
- 156 KB
- Volume
- 67
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
In 1983 C.
Thomassen conjectured that for every k, g ∈ N there exists d such that any graph with average degree at least d contains a subgraph with average degree at least k and girth at least g. Kühn and Osthus [2004] proved the case g = 6. We give another proof for the case g = 6 which is based on a result of F üredi [1983] about hypergraphs. We also show that the analogous conjecture for directed graphs is true. ᭧ 2010 Wiley
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