Generating functions and the satisfiability threshold
نویسنده
چکیده
The 3-SAT problem consists in determining if a boolean formula with 3 literals per clause is satisfiable. When the ratio between the number of clauses and the number of variables increases, a threshold phenomenon is observed: the probability of satisfiability appears in simulations to decrease sharply from 1 to 0 in the neighbourghood of a threshold value, conjectured to be close to 4.25. Although the threshold has been proved to exist for the 2-SAT formulæ and for closely related problems like 3-XORSAT, there is still no precise mathematical characterization of the threshold phenomena involved in the 3-SAT problem.
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عنوان ژورنال:
- Discrete Mathematics & Theoretical Computer Science
دوره 6 شماره
صفحات -
تاریخ انتشار 2004