Finding Large Monochromatic Diameter Two Subgraphs
نویسنده
چکیده
Given a coloring of the edges of the complete graph on n vertices in k colors, by considering the neighbors of an arbitrary vertex it follows that there is a monochromatic diameter two subgraph on at least 1 + (n− 1)/k vertices. We show that for k ≥ 3 this is asymptotically best possible, and that for k = 2 there is always a monochromatic diameter two subgraph on at least ⌈ 3 4 n⌉ vertices, which again, is best possible.
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