Conservative reduction classes of Krom formulas
- 12 March 1982
- journal article
- Published by Cambridge University Press (CUP) in The Journal of Symbolic Logic
- Vol. 47 (1) , 110-130
- https://doi.org/10.2307/2273385
Abstract
A Krom formula of pure quantification theory is a formula in conjunctive normal form such that each conjunct is a disjunction of at most two atomic formulas or negations of atomic formulas. Every class of Krom formulas that is determined by the form of their quantifier prefixes and which is known to have an unsolvable decision problem for satisfiability is here shown to be a conservative reduction class. Therefore both the general satisfiability problem, and the problem of satisfiability in finite models, can be effectively reduced from arbitrary formulas to Krom formulas of these several prefix types.Keywords
This publication has 3 references indexed in Scilit:
- Semi-conservative reductionArchive for Mathematical Logic, 1977
- Computation: Finite and Infinite Machines.The American Mathematical Monthly, 1968
- The Decision Problem for a Class of First‐Order Formulas in Which all Disjunctions are BinaryMathematical Logic Quarterly, 1967