Implication Zroupoids and Identities of Associative Type

An algebra A=⟨A,→,0⟩, where → is binary and 0 is a constant, is called an implication zroupoid (I-zroupoid, for short) if A satisfies the identities: (x→y)→z≈[(z′→x)→(y→z)′]′ and 0′′≈0, where x′:=x→0, and I denotes the variety of all I-zroupoids. An I-zroupoid is symmetric if it satisfies x′′≈x and...

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Detalles Bibliográficos
Autores: Cornejo, Juan Manuel, Sankappanavar, Hanamantagouda P.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/91905
Acceso en línea:http://hdl.handle.net/11336/91905
Access Level:acceso abierto
Palabra clave:IMPLICATION ZRUPOID
VARIETY
IDENTITY OF ASSOCIATIVE TYPE
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:An algebra A=⟨A,→,0⟩, where → is binary and 0 is a constant, is called an implication zroupoid (I-zroupoid, for short) if A satisfies the identities: (x→y)→z≈[(z′→x)→(y→z)′]′ and 0′′≈0, where x′:=x→0, and I denotes the variety of all I-zroupoids. An I-zroupoid is symmetric if it satisfies x′′≈x and (x→y′)′≈(y→x′)′. The variety of symmetric I-zroupoids is denoted by S. An identity p≈q, in the groupoid language ⟨→⟩, is called an identity of associative type of length 3 if p and q have exactly 3 (distinct) variables, say x,y,z, and are grouped according to one of the two ways of grouping: (1) ⋆→(⋆→⋆) and (2) (⋆→⋆)→⋆, where ⋆ is a place holder for a variable. A subvariety of I is said to be of associative type of length 3, if it is defined, relative to I, by a single identity of associative type of length 3. In this paper we give a complete analysis of the mutual relationships of all subvarieties of I of associative type of length 3. We prove, in our main theorem, that there are exactly 8 such subvarieties of I that are distinct from each other and describe explicitly the poset formed by them under inclusion. As an application of the main theorem, we derive that there are three distinct subvarieties of the variety S, each defined, relative to S, by a single identity of associative type of length 3.