For X a hypergraph on vertex set V and t : X+ R+, set We give a simple proof, based on an argument of Pippenger and Spencer [19] of the following rather general statement. Theorem 1.5. Fix k and 1. Let X be a k-bounded hypergraph and t a fractional matching of X. Let, furthermore, c , , . . . , c,
On a Conjecture of Rödl and Voigt
✍ Scribed by P. Komjath; E.C. Milner
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 408 KB
- Volume
- 61
- Category
- Article
- ISSN
- 0095-8956
No coin nor oath required. For personal study only.
✦ Synopsis
We prove that if (\lambda) is an infinite cardinal number and (G) is any graph of cardinality (\kappa=\lambda^{+})which is a union of a finite number of forests, then there is a graph (H_{k}) of size (\kappa) (which does not depend upon (G) ) so that (H_{k} \rightarrow(G){k}^{1}). Rödl and Voight conjectured that there is such a graph (H{\kappa}) for the special case when (G) is the regular tree on (\kappa) in which every vertex has degree (\kappa). We also prove that if a graph is the union of (n) forests, then it has colouring number (2 n). 1994 Academic Press. Inc.
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