Sparse universal graphs
نویسندگان
چکیده
For every n, we describe an explicit construction of a graph on n vertices with at most O(n2− ) edges, for = 0.133 . . ., that contains every graph on n vertices with maximum degree 3 as a subgraph. It is easy to see that each such graph must have at least Ω(n 4 3 ) edges. We also show that the minimum number of edges of a graph that contains every graph with n edges as a subgraph is Θ( n 2 log2 n ). This improves a result of Babai, Chung, Erdös, Graham and Spencer.
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تاریخ انتشار 2002