SCIENCE CHINA Information Sciences, Volume 59, Issue 9: 092101(2016) https://doi.org/10.1007/s11432-016-5526-8

A novel weighting scheme for random $k$-SAT

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  • ReceivedSep 28, 2015
  • AcceptedNov 3, 2015
  • PublishedAug 23, 2016


Consider a random $k$-conjunctive normal form $F_{k}(n, rn)$ with $n$ variables and $rn$ clauses. We prove that if the probability that the formula $F_{k}(n, rn)$ is satisfiable tends to 0 as $n\rightarrow\infty$, then $r\geq2.83$, 8.09, 18.91, 40.81, and 84.87, for $k=3$, 4, 5, 6, and 7, respectively.

Funded by

National Natural Science Foundation of China(11371225)

Fund of the State Key Lab of Software Development Environment(SKLSDE-2015ZX-05)



This work was supported by National Natural Science Foundation of China (Grant No. 11371225) and Fund of the State Key Lab of Software Development Environment (Grant No. SKLSDE-2015ZX-05).


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