Improved Bounds for Covering Complete Uniform Hypergraphs
نویسنده
چکیده
We consider the problem of covering the complete r-uniform hypergraphs on n vertices using complete r-partite graphs. We obtain lower bounds on the size of such a covering. For small values of r our result implies a lower bound of Ω( e r r √ r n log n) on the size of any such covering. This improves the previous bound of Ω(rn log n) due to Snir [5]. We also obtain good lower bounds on the size of a family of perfect hash function using simple arguments.
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 41 شماره
صفحات -
تاریخ انتشار 1992