The Existential Theory of Equations with Rational Constraints in Free Groups is PSPACE—Complete
This paper extends extends known results on the complexity of word equations and equations in free groups in order to include the presence of rational constraints, i.e., such that a possible solution has to respect a specification given by a rational language. Our main result states that the existential theory of equations with rational constraints in free groups is PSPACE-complete.
KeywordsFormal languages equations regular language free group
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