Explicit representation of terms defined by counter examples
Journal of Automated Reasoning
Equational problems anddisunification
Journal of Symbolic Computation
Equational formulae with membership constraints
Information and Computation
Negation elimination in empty of permutative theories
Journal of Symbolic Computation
An Efficient Unification Algorithm
ACM Transactions on Programming Languages and Systems (TOPLAS)
The Explicit Representability of Implicit Generalizations
RTA '00 Proceedings of the 11th International Conference on Rewriting Techniques and Applications
The Negation Elimination from Syntactic Equational Formula is Decidable
RTA '93 Proceedings of the 5th International Conference on Rewriting Techniques and Applications
An Improved Lower Bound for the Elementary Theories of Trees
CADE-13 Proceedings of the 13th International Conference on Automated Deduction: Automated Deduction
Working with Arms: Complexity Results on Atomic Representations of Herbrand Models
LICS '99 Proceedings of the 14th Annual IEEE Symposium on Logic in Computer Science
| Hi-index | 0.00 |
Equational formulae are first-order formulae over an alphabet F of function symbols whose only predicate symbol is syntactic equality. Unification problems are an important special case of equational formulae, where no universal quantifiers and no negation occur. By the negation elimination problem we mean the problem of deciding whether a given equational formula is semantically equivalent to a unification problem. This decision problem has many interesting applications in machine learning, logic programming, functional programming, constrained rewriting, etc. In this work we present a new algorithm for the negation elimination problem of equational formulae with purely existential quantifier prefix. Moreover, we prove the coNP-completeness for equational formulae in DNF and the Π2p-hardness in case of CNF.