Edward Hirsch

Recently there was a significant progress in

proving (exponential-time) worst-case upper bounds for the

propositional satisfiability problem (SAT).

MAX-SAT is an important generalization of SAT.

Several upper bounds were obtained for MAX-SAT and

its NP-complete subproblems.

In particular, Niedermeier and Rossmanith recently

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Uriel Feige, Marek Karpinski, Michael Langberg

We analyze the addition of a simple local improvement step to various known

randomized approximation algorithms.

Let $\alpha \simeq 0.87856$ denote the best approximation ratio currently

known for the Max Cut problem on general graphs~\cite{GW95}.

We consider a semidefinite relaxation of the Max Cut problem,

round it using the ...
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Piotr Berman, Marek Karpinski

We improve a number of approximation lower bounds for

bounded occurrence optimization problems like MAX-2SAT,

E2-LIN-2, Maximum Independent Set and Maximum-3D-Matching.

Piotr Berman, Marek Karpinski, Alexander D. Scott

We study approximation hardness and satisfiability of bounded

occurrence uniform instances of SAT. Among other things, we prove

the inapproximability for SAT instances in which every clause has

exactly 3 literals and each variable occurs exactly 4 times,

and display an explicit ...
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Ruiwen Chen, Rahul Santhanam

We give improved deterministic algorithms solving sparse instances of MAX-SAT and MAX-$k$-CSP. For instances with $n$ variables and $cn$ clauses (constraints), we give algorithms running in time $\poly(n)\cdot 2^{n(1-\mu)}$ for

\begin{itemize}

\item $\mu = \Omega(\frac{1}{c} )$ and polynomial space solving MAX-SAT and MAX-$k$-SAT,

\item $\mu = \Omega(\frac{1}{\sqrt{c}} )$ and ...
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