Extremal Graph Problems, Degenerate Extremal Problems, and Supersaturated Graphs
نویسنده
چکیده
Notation. Given a graph, hypergraph Gn, . . . , the upper index always denotes the number of vertices, e(G), v(G) and χ(G) denote the number of edges, vertices and the chromatic number of G respectively. Given a family L of graphs, hypergraphs, ex(n,L) denotes the maximum number of edges (hyperedges) a graph (hypergraph)Gn of order n can have without containing subgraphs (subhypergraphs) from L. The problem of determining ex(n,L) is called a Turán-type extremal problem. The graphs attaining the maximum will be called extremal and their family will be denoted by EX(n,L).
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تاریخ انتشار 2010