The number of k-SAT functions
نویسندگان
چکیده
We study the number SAT(k;n) of Boolean functions of n variables that can be expressed by a k-SAT formula. Equivalently, we study the number of subsets of the n-cube 2n that can be represented as the union of (n− k)-subcubes. In [3] the authors and Imre Leader studied SAT(k;n) for k ≤ n/2, with emphasis on the case k = 2. Here, we prove bounds on SAT(k;n) for k ≥ n/2; we see a variety of different types of behaviour. ∗email: [email protected], partially supported by NSF grant DMS-9971788 and DARPA grant F33615-01-C-1900 †email: [email protected]
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عنوان ژورنال:
- Random Struct. Algorithms
دوره 22 شماره
صفحات -
تاریخ انتشار 2003