3-SAT Faster and Simpler - Unique-SAT Bounds for PPSZ Hold in General

Timon Hertli

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arXiv · 1103.2165

3-SAT Faster and Simpler - Unique-SAT Bounds for PPSZ Hold in General

Timon Hertli

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Abstract

The PPSZ algorithm by Paturi, Pudlák, Saks, and Zane [1998] is the fastest known algorithm for Unique k-SAT, where the input formula does not have more than one satisfying assignment. For k>=5 the same bounds hold for general k-SAT. We show that this is also the case for k=3,4, using a slightly modified PPSZ algorithm. We do the analysis by defining a cost for satisfiable CNF formulas, which we prove to decrease in each PPSZ step by a certain amount. This improves our previous best bounds with Moser and Scheder [2011] for 3-SAT to O(1.308^n) and for 4-SAT to O(1.469^n).

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Timon Hertli. 2011-05-05. 3-SAT Faster and Simpler - Unique-SAT Bounds for PPSZ Hold in General. https://arxiv.org/abs/1103.2165

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