An upper bound on the sum of squares of degrees in a hypergraph
نویسنده
چکیده
We give an upper bound on the sum of squares of ‘-degrees in a k-uniform hypergraph in terms of ‘; k and the number of vertices and edges of the hypergraph, where a ‘-degree is the number of edges of the hypergraph containing a 0xed ‘-element subset of the vertices. For ordinary graphs this bound coincides with one given by de Caen. We show that our bound implies the quadratic LYM-inequality for 2-level antichains of subsets of a 0nite set. c © 2003 Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Mathematics
دوره 269 شماره
صفحات -
تاریخ انتشار 2003