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When quoting this document, please refer to the following
DOI: 10.4230/LIPIcs.STACS.2011.237
URN: urn:nbn:de:0030-drops-30147
URL: http://dagstuhl.sunsite.rwth-aachen.de/volltexte/2011/3014/
Hertli, Timon ;
Moser, Robin A. ;
Scheder, Dominik
Improving PPSZ for 3-SAT using Critical Variables
Abstract
A critical variable of a satisfiable CNF formula is a variable that has the same value in all satisfying assignments. Using a simple case distinction on the fraction of critical variables of a CNF formula, we improve the running time for 3-SAT from O(1.32216^n) [Rolf 2006] to O(1.32153^n). Using a different approach, Iwama et al. very recently achieved a running time of O(1.32113^n). Our method nicely combines with theirs, yielding the currently fastest known algorithm with running time O(1.32065^n). We also improve the bound for 4-SAT from O(1.47390^n) [Hofmeister et al. 2002] to O(1.46928^n), where O(1.46981^n) can be obtained using the methods of Hofmeister and Rolf.
BibTeX - Entry
@InProceedings{hertli_et_al:LIPIcs:2011:3014,
author = {Timon Hertli and Robin A. Moser and Dominik Scheder},
title = {{Improving PPSZ for 3-SAT using Critical Variables}},
booktitle = {28th International Symposium on Theoretical Aspects of Computer Science (STACS 2011) },
pages = {237--248},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-939897-25-5},
ISSN = {1868-8969},
year = {2011},
volume = {9},
editor = {Thomas Schwentick and Christoph D{\"u}rr},
publisher = {Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik},
address = {Dagstuhl, Germany},
URL = {http://drops.dagstuhl.de/opus/volltexte/2011/3014},
URN = {urn:nbn:de:0030-drops-30147},
doi = {10.4230/LIPIcs.STACS.2011.237},
annote = {Keywords: SAT, satisfiability, randomized, exponential time, algorithm, 3-SAT, 4-SAT}
}
Keywords: |
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SAT, satisfiability, randomized, exponential time, algorithm, 3-SAT, 4-SAT |
Collection: |
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28th International Symposium on Theoretical Aspects of Computer Science (STACS 2011) |
Issue Date: |
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2011 |
Date of publication: |
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11.03.2011 |