- Tytuł:
- Some modifications of congruence permutability and dually congruence regular varietie
- Autorzy:
-
Chajda, Ivan
Eigenthaler, Günther - Powiązania:
- https://bibliotekanauki.pl/articles/728754.pdf
- Data publikacji:
- 2001
- Wydawca:
- Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
- Tematy:
-
congruence regularity
local congruence regularity
dual congruence regularity
local n-permutability - Opis:
- It is well known that every congruence regular variety is n-permutable (in the sense of [9]) for some n ≥ 2. For the explicit proof see e.g. [2]. The connections between this n and Mal'cev type characterizations of congruence regularity were studied by G.D. Barbour and J.G. Raftery [1]. The concept of local congruence regularity was introduced in [3]. A common generalization of congruence regularity and local congruence regularity was given in [6] under the name "dual congruence regularity with respect to a unary term g". The natural problem arises what modification of n-permutability is satisfied by dually congruence regular varieties. The aim of this paper is to find out such a modification, to characterize varieties satisfying it by a Mal'cev type condition and to show connections with normally presented varieties (see e.g. [5], [8], [11]). The latter concept was introduced already by J. P≥onka under a different term; the names "normal identity" and "normal variety" were firstly used by E. Graczyńska in [8].
- Źródło:
-
Discussiones Mathematicae - General Algebra and Applications; 2001, 21, 2; 165-174
1509-9415 - Pojawia się w:
- Discussiones Mathematicae - General Algebra and Applications
- Dostawca treści:
- Biblioteka Nauki