Two weaker variants of congruence permutability for monoid varieties
نویسندگان
چکیده
منابع مشابه
Equations implying congruence n-permutability and semidistributivity
T. Dent, K. Kearnes and Á. Szendrei have defined the derivative, Σ′, of a set of equations Σ and shown, for idempotent Σ, that Σ implies congruence modularity if Σ′ is inconsistent (Σ′ |= x ≈ y). In this paper we investigate other types of derivatives that give similar results for congruence n-permutability for some n, and for congruence semidistributivity.
متن کاملNOTES ON CONGRUENCE n-PERMUTABILITY AND SEMIDISTRIBUTIVITY
In [1] T. Dent, K. Kearnes and Á. Szendrei define the derivative, Σ′, of a set of equations Σ and show, for idempotent Σ, that Σ implies congruence modularity if Σ′ is inconsistent (Σ′ |= x ≈ y). In this paper we investigate other types of derivatives that give similar results for congruence n-permutable for some n, and for congruence semidistributivity. In a recent paper [1] T. Dent, K. Kearne...
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ژورنال
عنوان ژورنال: Semigroup Forum
سال: 2021
ISSN: 0037-1912,1432-2137
DOI: 10.1007/s00233-021-10196-9