Ramsey Properties of Random Graphs and Folkman Numbers
Discussiones Mathematicae. Graph Theory, Tome 37 (2017) no. 3, pp. 755-776.

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For two graphs, G and F, and an integer r ≥ 2 we write G → (F)r if every r-coloring of the edges of G results in a monochromatic copy of F. In 1995, the first two authors established a threshold edge probability for the Ramsey property G(n, p) → (F)r, where G(n, p) is a random graph obtained by including each edge of the complete graph on n vertices, independently, with probability p. The original proof was based on the regularity lemma of Szemerédi and this led to tower-type dependencies between the involved parameters. Here, for r = 2, we provide a self-contained proof of a quantitative version of the Ramsey threshold theorem with only double exponential dependencies between the constants. As a corollary we obtain a double exponential upper bound on the 2-color Folkman numbers. By a different proof technique, a similar result was obtained independently by Conlon and Gowers.
Keywords: Ramsey property, random graph, Folkman number
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Rödl, Vojtěch; Ruciński, Andrzej; Schacht, Mathias. Ramsey Properties of Random Graphs and Folkman Numbers. Discussiones Mathematicae. Graph Theory, Tome 37 (2017) no. 3, pp. 755-776. http://geodesic.mathdoc.fr/item/DMGT_2017_37_3_a17/

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