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Related papers: Small unsatisfiable $k$-CNFs with bounded literal …

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We consider the following problem. Given a 2-CNF formula, is it possible to remove at most $k$ clauses so that the resulting 2-CNF formula is satisfiable? This problem is known to different research communities in Theoretical Computer…

Data Structures and Algorithms · Computer Science 2008-04-18 Igor Razgon , Barry O'Sullivan

We demonstrate a family of propositional formulas in conjunctive normal form so that a formula of size $N$ requires size $2^{\Omega(\sqrt[7]{N/logN})}$ to refute using the tree-like OBDD refutation system of Atserias, Kolaitis and Vardi…

Computational Complexity · Computer Science 2007-05-23 Nathan Segerlind

We present a method to gradually compute a smaller and smaller unsatisfiable core of a propositional formula by minimizing proofs of unsatisfiability. The goal is to compute a minimal unsatisfiable core that is relatively small compared to…

Logic in Computer Science · Computer Science 2019-07-16 Marijn J. H. Heule

Knuth (1990) introduced the class of nested formulas and showed that their satisfiability can be decided in polynomial time. We show that, parameterized by the size of a smallest strong backdoor set to the target class of nested formulas,…

Data Structures and Algorithms · Computer Science 2012-03-07 Serge Gaspers , Stefan Szeider

A novel parallel algorithm for solving the classical Decision Boolean Satisfiability problem with clauses in conjunctive normal form is depicted. My approach for solving SAT is without using algebra or other computational search strategies…

Data Structures and Algorithms · Computer Science 2018-04-17 Carlos Barrón-Romero

We aim at providing a foundation of a theory of "good" SAT representations F of boolean functions f. We argue that the hierarchy UC_k of unit-refutation complete clause-sets of level k, introduced by the authors, provides the most basic…

Artificial Intelligence · Computer Science 2013-05-13 Matthew Gwynne , Oliver Kullmann

We answer two open questions by (Gruber, Holzer, Kutrib, 2009) on the state-complexity of representing sub- or superword closures of context-free grammars (CFGs): (1) We prove a (tight) upper bound of $2^{\mathcal{O}(n)}$ on the size of…

Formal Languages and Automata Theory · Computer Science 2014-10-24 Georg Bachmeier , Michael Luttenberger , Maximilian Schlund

Given a CNF formula F on n variables, the problem of model counting or #SAT is to compute the number of satisfying assignments of F . Model counting is a fundamental but hard problem in computer science with varied applications. Recent…

Data Structures and Algorithms · Computer Science 2020-05-01 Kuldeep S. Meel , S. Akshay

We consider the regular model of formula generation in conjunctive normal form (CNF) introduced by Boufkhad et. al. We derive an upper bound on the satisfiability threshold and NAE-satisfiability threshold for regular random $k$-SAT for any…

Information Theory · Computer Science 2010-04-26 Vishwambhar Rathi , Erik Aurell , Lars Rasmussen , Mikael Skoglund

We establish the satisfiability threshold for random $k$-SAT for all $k\ge k_0$, with $k_0$ an absolute constant. That is, there exists a limiting density $\alpha_*(k)$ such that a random $k$-SAT formula of clause density $\alpha$ is with…

Probability · Mathematics 2021-04-16 Jian Ding , Allan Sly , Nike Sun

The study of regular linear conjunctive normal form (LCNF) formulas is of interest because exact satisfiability (XSAT) is known to be NP-complete for this class of formulas. In a recent paper it was shown that the subclass of regular exact…

Computational Complexity · Computer Science 2018-12-24 Bernd R. Schuh

We consider the question of the existence of variables with few occurrences in boolean conjunctive normal forms (clause-sets). Let mvd(F) for a clause-set F denote the minimal variable-degree, the minimum of the number of occurrences of…

Discrete Mathematics · Computer Science 2014-06-24 Oliver Kullmann , Xishun Zhao

Maximum Satisfiability (MaxSAT) is a well-known optimization pro- blem, with several practical applications. The most widely known MAXS AT algorithms are ineffective at solving hard problems instances from practical application domains.…

Artificial Intelligence · Computer Science 2007-12-10 Joao Marques-Silva , Jordi Planes

Given a 2-SAT formula $F$ consisting of $n$ variables and $\cn$ random clauses, what is the largest number of clauses $\max F$ satisfiable by a single assignment of the variables? We bound the answer away from the trivial bounds of…

Combinatorics · Mathematics 2016-09-07 Don Coppersmith , David Gamarnik , Mohammad Hajiaghayi , Gregory B. Sorkin

A heuristic model procedure for determining satisfiability of CNF-formulae is set up and described by nonlinear recursion relations for m (number of clauses), n (number of variables) and clause filling k. The system mimicked by the…

Computational Complexity · Computer Science 2014-11-12 Bernd R. Schuh

Let $\Phi$ be a random $k$-CNF formula on $n$ variables and $m$ clauses, where each clause is a disjunction of $k$ literals chosen independently and uniformly. Our goal is to sample an approximately uniform solution of $\Phi$ (or…

Data Structures and Algorithms · Computer Science 2023-06-12 Kun He , Kewen Wu , Kuan Yang

We focus on the random generation of SAT instances that have properties similar to real-world instances. It is known that many industrial instances, even with a great number of variables, can be solved by a clever solver in a reasonable…

Computational Complexity · Computer Science 2023-03-14 Carlos Ansótegui , Maria Luisa Bonet , Jordi Levy

Random $k$-SAT is the single most intensely studied example of a random constraint satisfaction problem. But despite substantial progress over the past decade, the threshold for the existence of satisfying assignments is not known precisely…

Combinatorics · Mathematics 2017-11-29 Amin Coja-Oghlan , Konstantinos Panagiotou

In this work we suggest a new model for generating random satisfiable k-CNF formulas. To generate such formulas -- randomly permute all 2^k\binom{n}{k} possible clauses over the variables x_1, ..., x_n, and starting from the empty formula,…

Combinatorics · Mathematics 2008-07-29 Michael Krivelevich , Benny Sudakov , Dan Vilenchik

This paper describes a novel unbounded software model checking approach to find errors in programs written in the C language based on incremental SAT-solving. Instead of using the traditional assumption based API to incremental SAT solvers…

Symbolic Computation · Computer Science 2018-02-14 Marko Kleine Büning , Tomas Balyo , Carsten Sinz
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