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Related papers: Unsatisfiable Linear k-CNFs Exist, for every k

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A central task in knowledge compilation is to compile a CNF-SAT instance into a succinct representation format that allows efficient operations such as testing satisfiability, counting, or enumerating all solutions. Useful representation…

Logic in Computer Science · Computer Science 2024-10-07 Christoph Berkholz , Stefan Mengel , Hermann Wilhelm

The runtime performance of modern SAT solvers on random $k$-CNF formulas is deeply connected with the 'phase-transition' phenomenon seen empirically in the satisfiability of random $k$-CNF formulas. Recent universal hashing-based approaches…

Discrete Mathematics · Computer Science 2017-02-28 Jeffrey M. Dudek , Kuldeep S. Meel , Moshe Y. Vardi

Two CNF formulas are called ucp-equivalent, if they behave in the same way with respect to the unit clause propagation (UCP). A formula is called ucp-irredundant, if removing any clause leads to a formula which is not ucp-equivalent to the…

Combinatorics · Mathematics 2026-02-09 Petr Savický

We study the complexity of the following "resolution width problem": Does a given 3-CNF have a resolution refutation of width k? We prove that the problem cannot be decided in time O(n^((k-3)/12)). This lower bound is unconditional and does…

Logic in Computer Science · Computer Science 2015-03-20 Christoph Berkholz

The basic random $k$-SAT problem is: Given a set of $n$ Boolean variables, and $m$ clauses of size $k$ picked uniformly at random from the set of all such clauses on our variables, is the conjunction of these clauses satisfiable? Here we…

Combinatorics · Mathematics 2019-06-13 Joel Larsson , Klas Markström

We discuss the natural range of the Unambiguous-SAT problem with respect to the number of clauses. We prove that for a given Boolean formula in precise conjunctive normal form with n variables, there exist functions f(n) and g(n) such that…

Computational Complexity · Computer Science 2024-11-25 Tayfun Pay

Let $\phi$ be a 3CNF formula with n variables and m clauses. A simple nonconstructive argument shows that when m is sufficiently large compared to n, most 3CNF formulas are not satisfiable. It is an open question whether there is an…

Computational Complexity · Computer Science 2007-05-23 Uriel Feige , Eran Ofek

The satisfiability problem is NP-complete but there are subclasses where all the instances are satisfiable. For this, restrictions on the shape of the formula are made. Darman and D\"ocker show that the subclass MONOTONE $3$-SAT-($k$,1)…

Computational Complexity · Computer Science 2023-12-11 Hannah Van Santvliet , Ronald de Haan

In this paper, we analyze the argument made by Kumar in the technical report "Necessary and Sufficient Condition for Satisfiability of a Boolean Formula in CNF and Its Implications on P versus NP problem." The paper claims to present a…

Computational Complexity · Computer Science 2021-12-14 Michael C. Chavrimootoo , Henry B. Welles

In this work we propose and analyze a simple randomized algorithm to find a satisfiable assignment for a Boolean formula in conjunctive normal form (CNF) having at most 3 literals in every clause. Given a k-CNF formula phi on n variables,…

Data Structures and Algorithms · Computer Science 2020-08-11 Subhas Kumar Ghosh , Janardan Misra

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

The satisfiability problem is known to be $\mathbf{NP}$-complete in general and for many restricted cases. One way to restrict instances of $k$-SAT is to limit the number of times a variable can be occurred. It was shown that for an…

Discrete Mathematics · Computer Science 2023-06-22 Arash Ahadi , Ali Dehghan

There has been much recent interest in the satisfiability of random Boolean formulas. A random k-SAT formula is the conjunction of m random clauses, each of which is the disjunction of k literals (a variable or its negation). It is known…

Probability · Mathematics 2012-06-19 David B. Wilson

A matched formula is a CNF formula whose incidence graph admits a matching which matches a distinct variable to every clause. We study phase transition in a context of matched formulas and their generalization of biclique satisfiable…

Data Structures and Algorithms · Computer Science 2018-08-07 Miloš Chromý , Petr Kučera

The Local Lemma is a fundamental tool of probabilistic combinatorics and theoretical computer science, yet there are hardly any natural problems known where it provides an asymptotically tight answer. The main theme of our paper is to…

Combinatorics · Mathematics 2016-04-21 Heidi Gebauer , Tibor Szabo , Gabor Tardos

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

Quantified Boolean Formula (QBF) is a notoriously hard generalization of \textsc{SAT}, especially from the point of view of parameterized complexity, where the problem remains intractable for most standard parameters. A recent work by…

Computational Complexity · Computer Science 2026-03-11 Andreas Grigorjew , Michael Lampis

In the Longest Common Factor with $k$ Mismatches (LCF$_k$) problem, we are given two strings $X$ and $Y$ of total length $n$, and we are asked to find a pair of maximal-length factors, one of $X$ and the other of $Y$, such that their…

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 Achlioptas processes for k-SAT formulas. We create a semi-random formula with n variables and m clauses, where each clause is a choice, made on-line, between two or more uniformly random clauses. Our goal is to delay the…

Computational Complexity · Computer Science 2012-12-03 Varsha Dani , Josep Diaz , Thomas Hayes , Cristopher Moore