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CNF (Definition)

A propositional formula is a CNF formula, meaning Conjunctive Normal Form, if it is a conjunction of disjunction of literals (a literal is a propositional variable or its negation). Hence, a CNF is a formula of the form: $ K_1 \wedge K_2 \wedge \ldots \wedge K_n$, where each $ K_i$ is of the form $ l_{i1} \vee l_{i2} \vee \ldots \vee l_{im}$ for literals $ l_{ij}$ and some $ m$ (which can vary for each $ K_i$).

Example: $ (x\vee y \vee \neg z) \wedge (y\vee \neg w \vee \neg u) \wedge (x\vee v)$.



"CNF" is owned by rspuzio. [ owner history (1) ]
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See Also: DNF, atomic formula

Other names:  conjunctive normal form
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Cross-references: negation, variable, literals, disjunction, conjunction, formula
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This is version 4 of CNF, born on 2003-10-16, modified 2004-03-09.
Object id is 5392, canonical name is CNF.
Accessed 3934 times total.

Classification:
AMS MSC: 03B05 (Mathematical logic and foundations :: General logic :: Classical propositional logic)
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