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Efficient Recognition of Random Unsatisfiable k-SAT Instances by Spectral Methods

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STACS 2001 (STACS 2001)

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Abstract

It is known that random k-SAT instances with at least cn clauses where c = c k is a suitable constant are unsatisfiable (with high probability). We consider the problem to certify efficiently the unsatis- fiability of such formulas. A result of Beame et al. shows that k-SAT instances with at least n k-1= log n clauses can be certified unsatisfiable in polynomial time. We employ spectral methods to improve on this: We present a polynomial time algorithm which certifies random k-SAT instances for k even with at least 2k . (k/2)7 . (ln n)7 . n k/2 = n (k/2)+o(1) clauses as unsatisfiable (with high probability).

Partially supported by a USA-Israeli BSF grant.

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Goerdt, A., Krivelevich, M. (2001). Efficient Recognition of Random Unsatisfiable k-SAT Instances by Spectral Methods. In: Ferreira, A., Reichel, H. (eds) STACS 2001. STACS 2001. Lecture Notes in Computer Science, vol 2010. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-44693-1_26

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  • DOI: https://doi.org/10.1007/3-540-44693-1_26

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