Some decidable theories with finitely many covers which are decidable and algorithmically found

• Autorzy: Cornelia Kalfa
• Języki publikacji: EN

Abstrakty

EN

In any recursive algebraic language, I find an interval of the lattice of equational theories, every element of which has finitely many covers. With every finite set of equations of this language, an equational theory of this interval is associated, which is decidable with decidable covers that can be algorithmically found. If the language is finite, both this theory and its covers are finitely based. Also, for every finite language and for every natural number n, I construct a finitely based decidable theory together with its exactly n covers which are decidable and finitely based. The construction is algorithmic.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Colloquium Mathematicum
• Rocznik: 1994
• Tom: 67
• Numer: 1
• Strony: 61-67

Daty

wydano

1994

otrzymano

1993-05-05

poprawiono

1993-09-02

Twórcy

autor

Cornelia Kalfa

• Department of Mathematics, Faculty of Science, Aristotle University, Thessaloniki, Greece

Bibliografia

• [1] A. Ehrenfeucht, Decidability at the theory of one function, Notices Amer. Math. Soc. 6 (1959), 268.
• [2] J. Ježek, Primitive classes of algebras with unary and nullary operations, Colloq. Math. 20 (1969), 159-179.
• [3] C. Kalfa, Covering relation in the language of mono-unary algebras with at most one constant symbol, Algebra Universalis 26 (1989), 143-148.
• [4] G. F. McNulty, Covering in the lattice of equational theories and some properties of term finite theories, ibid. 15 (1982), 115-125.