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arXiv · 0705.0325

The order of the largest complete minor in a random graph

N. Fountoulakis·D. Kühn·D. Osthus
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Abstract

Let ccl(G) denote the order of the largest complete minor in a graph G (also called the contraction clique number) and let G(n,p) denote a random graph on n vertices with edge probability p. Bollobas, Catlin and Erdos asymptotically determined ccl(G (n,p)) when p is a constant. Luczak, Pittel and Wierman gave bounds on ccl(G(n,p)) when p is very close to 1/n, i.e. inside the phase transition. Extending the results of Bollobas, Catlin and Erdos, we determine ccl(G(n,p)) quite tightly, for p>C/n where C is a large constant. If p=C/n, for an arbitrary constant C>1, then we show that asymptotically almost surely ccl(G (n,p)) is of order square-root of n. This answers a question of Krivelevich and Sudakov.

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N. Fountoulakis, D. Kühn, D. Osthus. 2007-05-02. The order of the largest complete minor in a random graph. https://arxiv.org/abs/0705.0325

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