Interval Number and Boxicity of Directed Graphs
نویسنده
چکیده
We introduce interval number and boxicity for digraphs, analogous to the corresponding concepts for graphs. The results are: 1) i(D) maxf + (D); ? (D)g, which is sharp. 2) The largest interval number of an n-vertex digraph is between (1?o(1)) n 4lg 2n and n lg n + 2. 3) The largest boxicity of an n-vertex digraph is dn=2e.
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