| author: | John Talbot |
|---|---|
| title: |
Chromatic Turán problems and a new upper bound for
the Turán density of
K
4
-
|
| keywords: | Extremal combinatorics, Turán-type problems, Hypergraphs |
| abstract: |
We consider a new type of extremal hypergraph problem:
given an
r
-graph
F
k≥2
determine the maximum number of edges in an
F
k
-colourable
r
-graph on
n
vertices. Our motivation for studying such problems
is that it allows us to give a new upper bound for an old
problem due to Turán. We show that a
3
-graph in which any four vertices span at most two
edges has density less than
33 / 100
, improving previous bounds of
1 / 3
due to de Caen [deC], and
1 / 3-4.5305×10
due to Mubayi [M].
-6
|
| If your browser does not display the abstract correctly (because of the different mathematical symbols) you may look it up in the PostScript or PDF files. | |
| reference: |
John Talbot (2005), Chromatic Turán problems and a
new upper bound for the Turán density of
K
, in 2005 European Conference on Combinatorics,
Graph Theory and Applications (EuroComb '05), Stefan
Felsner (ed.), Discrete Mathematics and Theoretical
Computer Science Proceedings AE, pp. 77-80
4
-
|
| bibtex: | For a corresponding BibTeX entry, please consider our BibTeX-file. |
| ps.gz-source: | dmAE0116.ps.gz (56 K) |
| ps-source: | dmAE0116.ps (134 K) |
| pdf-source: | dmAE0116.pdf (134 K) |
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