We give a randomized algorithm for testing satisfiability of Boolean formulas in conjunctive normal form with no restriction on clause length. Its running time is at most $2^{n(1-1/\alpha)}$ up to a polynomial factor, where $\alpha = \ln(m/n) + O(\ln \ln m)$ and $n$, $m$ are respectively the number of variables ... more >>>

We give faster approximation algorithms for the
generalization of two NP-hard spanning tree problems. First,
we investigate the problem of minimizing the degree of
minimum spanning forests. The task is to compute for each
number of connected components a minimum spanning forest
whose degree is as small as possible. Fischer
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A clone is a set of functions that is closed under generalized substitution.
The set FP of functions being computable deterministically in polynomial
time is such a clone. It is well-known that the set of subclones of every
clone forms a lattice. We study the lattice below FP, which ... more >>>