A Note on Turán Numbers for Even Wheels
نویسنده
چکیده
The Turán number ex(n,G) is the maximum number of edges in any n-vertex graph that does not contain a subgraph isomorphic to G. We consider a very special case of the Simonovits’s theorem (Simonovits in: Theory of graphs, Academic Press, New York, 1968) which determine an asymptotic result for Turán numbers for graphs with some properties. In the paper we present a more precise result for even wheels. We provide the exact value for Turán number ex(n, W2k) for n ≥ 6k − 10 and k ≥ 3. In addition, we show that ex(n, W6) = n2 3 for all n ≥ 6. These numbers can be useful to calculate some Ramsey numbers.
منابع مشابه
The Ramsey numbers of large trees versus wheels
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عنوان ژورنال:
- Graphs and Combinatorics
دوره 29 شماره
صفحات -
تاریخ انتشار 2013