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A Simple Functional Presentation and an Inductive Correctness Proof of the Horn Algorithm

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 نشر من قبل EPTCS
 تاريخ النشر 2018
  مجال البحث الهندسة المعلوماتية
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We present a recursive formulation of the Horn algorithm for deciding the satisfiability of propositional clauses. The usual presentations in imperative pseudo-code are informal and not suitable for simple proofs of its main properties. By defining the algorithm as a recursive function (computing a least fixed-point), we achieve: 1) a concise, yet rigorous, formalisation; 2) a clear form of visualising executions of the algorithm, step-by-step; 3) precise results, simple to state and with clean inductive proofs.



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