WikiProject Mathematics  (Rated Startclass, Lowimportance)  


Bah. Conjunctive normal form is not a method. There is a method to construct a conjunctive normal form of a logical function, but the CNF, the result of this method is not the method. A method is not the same as the result of this. Be exact, please :)) (a mathematician). Gubbubu 20:44, 28 May 2005 (UTC)
If 4SAT is defined like 3SAT (all clauses have at most 4 literals), the problem is NPcomplete, like any other kSAT problem with k>2. The recent edit stating that 4SAT is linear is incorrect unless a different definition of 4SAT is considered. Source?  Liberatore(T) 15:25, 16 December 2005 (UTC)
Regarding the following line:
Transformations of formulae in CNF form preserving satisfiability (rather than equivalence) and introducing new variables exist. These transformations are interesting because they are guaranteed not to produce an exponential blowup.
I am curious as to the source of this statement. I am particularly interested in reading what these transformations are specifically. Stux 06:48, 2 January 2006 (UTC)
I have been studying boolean algebra in my class "Fundamentals of Logic Design", and we are taught that CNF is more than just product of sums. We are taught that every sum (clause) must contain every literal. *This* is what makes the form useful for comparing functions and performing automatic analysis. Please comment, i'm interested to know how this is formally defined and used. Fresheneesz 21:05, 6 February 2006 (UTC)
I'm not quite sure, but in my Logic class I've been told that is actually in DNF, and not CNF, because it is a single literal (i.e. equivalent to ). Can someone provide a counterexample if this is false or change the page if not? Poromenos (talk) 11:36, 13 February 2008 (UTC)
Shouldn't it be "distribute ORs over ANDs"? Where i am interpreting "distribute ANDs over ORs" to mean the act of converting things like "A AND (B OR C)" into things like "(A AND B) OR (A AND C)". Bayle Shanks (talk) 10:23, 24 January 2010 (UTC)
It appears that a step is missing. While converting, the second step should be to move ¬ inward. Preceding unsigned comment added by Loki411 (talk o contribs) 07:31, 10 November 2010 (UTC)
I don't believe this should be merged. Olleicua (talk) 16:48, 29 September 2011 (UTC)
I think it can be merged, over various internet sources both are treated same.. AshutoshJuve (talk) 17:01, 6 December 2011 (UTC)
Conjunctive normal form and clausal normal form are indeed the same thing. See, for example, Melvin Fitting, First order logic and automated theorem proving, second edition, page 28. Thus I vote to merge 82.24.239.152 (talk) 19:56, 28 December 2012 (UTC)
Regarding the word "redices"  is that a word? LilHelpa (talk) 13:47, 16 May 2017 (UTC)
The method of converting a formula into a CNF is not introduced. Wxhtxdy (talk) 16:05, 9 March 2019 (UTC)