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The structure of the set of satisfying assignments for a random k-CNF

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Abstract

Let F k (n, m) be a random k-CNF obtained by a random, equiprobable, and independent choice of m brackets from among all k-literal brackets on n variables. We investigate the structure of the set of satisfying assignments of F k (n, m). A method is proposed for finding r(k, s)such that the probability of presence of ns-dimensional faces (0 < s < 1) in the set of satisfying assignments of the formula F k s(n, r(k, s)n) goes to 1 as n goes to infinity. We prove the existence of a sequential threshold for the property of having ns-dimensional faces (0 < s < 1). In other words, there exists a sequence r n (k, s) such that the probability of having an ns-dimensional face in the set of satisfying assignments of the formula F k (n, r n (k, s)(1 + d)n) goes to 0 for all d > 0 and to 1 for all d < 0.

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References

  1. D. Achlioptas and C. Moore, “The asymptotic order of the random k-SAT threshold,” Proc. 43 rd Annual Symp. Foundations of Computer Science, 126–127 (2002).

  2. D. Achlioptas and Y. Peres, “The threshold for random k-SAT is 2k ln 2 − O(k),” J. AMS, 17, 947–973 (2004).

    MATH  MathSciNet  Google Scholar 

  3. F. Yu. Vorob’ev, “Lower bound on the 4-satisfiability threshold,” Diskretnaya Matematika, 19, No. 2, 101–108 (2007).

    Google Scholar 

  4. E. Friedgut, “Sharp thresholds of graph properties and the k-SAT problem,” J. AMS, 12, 1017–1054 (1999).

    MATH  MathSciNet  Google Scholar 

  5. N. G. de Bruijn, Asymptotic Methods in Analysis, 3 rd ed., Dover, New York (1981).

    MATH  Google Scholar 

  6. V. Chvatal and B. Reed, “Mick gets some (the odds are on his side),” Proc. 33 rd Annual Symp. Foundations of Computer Science, 620–627 (1992).

  7. H. Daude, M. Mezard, T. Mora, and R. Zecchina, “Pairs of SAT assignments and clustering in random Boolean formulae,” arXiv:cond-mat/0506053 (2005).

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Correspondence to F. Yu. Vorob’ev.

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Translated from Prikladnaya Matematika i Informatika, No. 26, pp. 61–95, 2007.

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Vorob’ev, F.Y. The structure of the set of satisfying assignments for a random k-CNF. Comput Math Model 19, 304–331 (2008). https://doi.org/10.1007/s10598-008-9006-x

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