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Related papers: The Threshold for Random k-SAT is 2^k ln2 - O(k)

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We prove that a random 3-SAT instance with clause-to-variable density less than 3.52 is satisfiable with high probability. The proof comes through an algorithm which selects (and sets) a variable depending on its degree and that of its…

Combinatorics · Mathematics 2007-05-23 MohammadTaghi Hajiaghayi , Gregory B. Sorkin

(k,s)-SAT is the satisfiability problem restricted to instances where each clause has exactly k literals and every variable occurs at most s times. It is known that there exists a function f such that for s\leq f(k) all (k,s)-SAT instances…

Combinatorics · Mathematics 2007-05-23 Shlomo Hoory , Stefan Szeider

Let $\Phi$ be a random $k$-SAT formula in which every variable occurs precisely $d$ times positively and $d$ times negatively. Assuming that $k$ is sufficiently large and that $d$ is slightly below the critical degree where the formula…

Combinatorics · Mathematics 2016-11-11 Amin Coja-Oghlan , Nick Wormald

The random $k$-SAT problem serves as a model that represents the 'typical' $k$-SAT instances. This model is thought to undergo a phase transition as the clause density changes, and it is believed that the random $k$-SAT problem is primarily…

Probability · Mathematics 2025-05-23 Andreas Basse-O'Connor , Mette Skjøtt

We study an Achlioptas-process version of the random k-SAT process: a bounded number of k-clauses are drawn uniformly at random at each step, and exactly one added to the growing formula according to a particular rule. We prove the…

Combinatorics · Mathematics 2013-10-16 Will Perkins

Consider a random $k$-CNF formula $F_{k}(n, rn)$ with $n$ variables and $rn$ clauses. For every truth assignment $\sigma\in \{0, 1\}^{n}$ and every clause $c=\ell_{1}\vee\cdots\vee\ell_{k}$, let $d=d(\sigma, c)$ be the number of satisfied…

Discrete Mathematics · Computer Science 2013-10-17 Zongsheng Gao , Jun Liu , Ke Xu

We present a new structural (or syntatic) approach for estimating the satisfiability threshold of random 3-SAT formulae. We show its efficiency in obtaining a jump from the previous upper bounds, lowering them to 4.506. The method combines…

Discrete Mathematics · Computer Science 2007-05-23 Olivier Dubois , Yacine Boufkhad , Jacques Mandler

To study the structure of solutions for random k-SAT and random CSPs, this paper introduces the concept of average similarity degree to characterize how solutions are similar to each other. It is proved that under certain conditions, as r…

Artificial Intelligence · Computer Science 2007-05-23 Ke Xu , Wei Li

It is well known that, as $n$ tends to infinity, the probability of satisfiability for a random 2-SAT formula on $n$ variables, where each clause occurs independently with probability $\alpha/2n$, exhibits a sharp threshold at $\alpha=1$.…

Probability · Mathematics 2009-05-20 Elchanan Mossel , Arnab Sen

The problem of identifying the satisfiability threshold of random $3$-SAT formulas has received a lot of attention during the last decades and has inspired the study of other threshold phenomena in random combinatorial structures. The…

Combinatorics · Mathematics 2024-11-07 Ioannis Caragiannis , Nick Gravin , Zhile Jiang

We present a deterministic approximation algorithm to compute logarithm of the number of `good' truth assignments for a random k-satisfiability (k-SAT) formula in polynomial time (by `good' we mean that violate a small fraction of clauses).…

Discrete Mathematics · Computer Science 2007-05-23 Andrea Montanari , Devavrat Shah

It has been hypothesized that $k$-SAT is hard to solve for randomly chosen instances near the "critical threshold", where the clause-to-variable ratio is $2^k \ln 2-\theta(1)$. Feige's hypothesis for $k$-SAT says that for all sufficiently…

Data Structures and Algorithms · Computer Science 2018-10-16 Nikhil Vyas

Let $A$ be a random $m\times n$ matrix over the finite field $F_q$ with precisely $k$ non-zero entries per row and let $y\in F_q^m$ be a random vector chosen independently of $A$. We identify the threshold $m/n$ up to which the linear…

Combinatorics · Mathematics 2022-07-28 Peter Ayre , Amin Coja-Oghlan , Pu Gao , Noëla Müller

Propositional satisfiability (SAT) is one of the most fundamental problems in computer science. The worst-case hardness of SAT lies at the core of computational complexity theory. The average-case analysis of SAT has triggered the…

Discrete Mathematics · Computer Science 2019-05-03 Tobias Friedrich , Anton Krohmer , Ralf Rothenberger , Thomas Sauerwald , Andrew M. Sutton

Random instances of constraint satisfaction problems such as k-SAT provide challenging benchmarks. If there are m constraints over n variables there is typically a large range of densities r=m/n where solutions are known to exist with…

Discrete Mathematics · Computer Science 2009-11-13 Amin Coja-Oghlan

We present the current fastest deterministic algorithm for $k$-SAT, improving the upper bound $(2-2/k)^{n + o(n)}$ dues to Moser and Scheder [STOC'11]. The algorithm combines a branching algorithm with the derandomized local search, whose…

Data Structures and Algorithms · Computer Science 2020-03-19 S. Cliff Liu

We give a nearly linear-time algorithm to approximately sample satisfying assignments in the random $k$-SAT model when the density of the formula scales exponentially with $k$. The best previously known sampling algorithm for the random…

Data Structures and Algorithms · Computer Science 2024-08-06 Zongchen Chen , Andreas Galanis , Leslie Ann Goldberg , Heng Guo , Andrés Herrera-Poyatos , Nitya Mani , Ankur Moitra

The random k-SAT model is the most important and well-studied distribution over k-SAT instances. It is closely connected to statistical physics; it is used as a testbench for satisfiability algorithms, and average-case hardness over this…

Computational Complexity · Computer Science 2017-03-08 Noah Fleming , Denis Pankratov , Toniann Pitassi , Robert Robere

Let $\varPhi$ be a uniformly distributed random $k$-SAT formula with $n$ variables and $m$ clauses. For clauses/variables ratio $m/n \leq r_{k\text{-SAT}} \sim 2^k\ln2$ the formula $\varPhi$ is satisfiable with high probability. However, no…

Data Structures and Algorithms · Computer Science 2016-03-01 Samuel Hetterich

We consider "unconstrained" random $k$-XORSAT, which is a uniformly random system of $m$ linear non-homogeneous equations in $\mathbb{F}_2$ over $n$ variables, each equation containing $k \geq 3$ variables, and also consider a "constrained"…

Combinatorics · Mathematics 2014-08-05 Boris Pittel , Gregory B. Sorkin