Using a technique of Erdos, we show that for any given M > 0 and e > 0,there exist δ = δ(M, ε) > 0 and a graph G of any large order n such that the density ofG is at least M, while the density of the subgraph induced by any subset U V(G) with|U| ≤δn is less than 1 + ε. The constant 1 + e cannot be improved to 1.
Local densityglobal densityrandom graph
Li Yusheng
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Department of Mathematics, Hohai University, Nanjing 210098, China