unsatisfiable formula

См. также в других словарях:

• Unsatisfiable core — In mathematical logic, given an unsatisfiable boolean propositional formula in conjunctive normal form, a subset of clauses whose conjunction is still unsatisfiable is called an unsatisfiable core of the original formula. Many SAT solvers can… …   Wikipedia

• Davis–Putnam algorithm — The Davis–Putnam algorithm was developed by Martin Davis and Hilary Putnam for checking the validity of a first order logic formula using a resolution based decision procedure for propositional logic. Since the set of valid first order formulas… …   Wikipedia

• Method of analytic tableaux — A graphical representation of a partially built propositional tableau In proof theory, the semantic tableau (or truth tree) is a decision procedure for sentential and related logics, and a proof procedure for formulas of first order logic. The… …   Wikipedia

• First-order logic — is a formal logical system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first order predicate calculus, the lower predicate calculus, quantification theory, and predicate logic (a less… …   Wikipedia

• Valiant-Vazirani theorem — The Valiant Vazirani Theorem was proven by Leslie Valiant and Vijay Vazirani in their paper titled NP is as easy as detecting unique solutions published in 1986. The theorem states that if there is a polynomial time algorithm for UNIQUE SAT, then …   Wikipedia

• Resolution (logic) — In mathematical logic and automated theorem proving, resolution is a rule of inference leading to a refutation theorem proving technique for sentences in propositional logic and first order logic. In other words, iteratively applying the… …   Wikipedia

• Tautology (logic) — In propositional logic, a tautology (from the Greek word ταυτολογία) is a propositional formula that is true under any possible valuation (also called a truth assignment or an interpretation) of its propositional variables. For example, the… …   Wikipedia

• Boolean satisfiability problem — For the concept in mathematical logic, see Satisfiability. 3SAT redirects here. For the Central European television network, see 3sat. In computer science, satisfiability (often written in all capitals or abbreviated SAT) is the problem of… …   Wikipedia

• 2-satisfiability — In computer science, 2 satisfiability (abbreviated as 2 SAT or just 2SAT) is the problem of determining whether a collection of two valued (Boolean or binary) variables with constraints on pairs of variables can be assigned values satisfying all… …   Wikipedia

• Model theory — This article is about the mathematical discipline. For the informal notion in other parts of mathematics and science, see Mathematical model. In mathematics, model theory is the study of (classes of) mathematical structures (e.g. groups, fields,… …   Wikipedia

• formal logic — the branch of logic concerned exclusively with the principles of deductive reasoning and with the form rather than the content of propositions. [1855 60] * * * Introduction       the abstract study of propositions, statements, or assertively used …   Universalium