Sankappanavar, H. (2014). Dually quasi-De Morgan Stone semi-Heyting algebras II. Regularity. Categories and General Algebraic Structures with Applications, 2(1), 65-82.

Hanamantagouda P. Sankappanavar. "Dually quasi-De Morgan Stone semi-Heyting algebras II. Regularity". Categories and General Algebraic Structures with Applications, 2, 1, 2014, 65-82.

Sankappanavar, H. (2014). 'Dually quasi-De Morgan Stone semi-Heyting algebras II. Regularity', Categories and General Algebraic Structures with Applications, 2(1), pp. 65-82.

Sankappanavar, H. Dually quasi-De Morgan Stone semi-Heyting algebras II. Regularity. Categories and General Algebraic Structures with Applications, 2014; 2(1): 65-82.

Dually quasi-De Morgan Stone semi-Heyting algebras II. Regularity

^{}Department of Mathematics, State University of New York, New Paltz, NY 12561

Abstract

This paper is the second of a two part series. In this Part, we prove, using the description of simples obtained in Part I, that the variety $mathbf{RDQDStSH_1}$ of regular dually quasi-De Morgan Stone semi-Heyting algebras of level 1 is the join of the variety generated by the twenty 3-element $mathbf{RDQDStSH_1}$-chains and the variety of dually quasi-De Morgan Boolean semi-Heyting algebras--the latter is known to be generated by the expansions of the three 4-element Boolean semi-Heyting algebras. As consequences of our main theorem, we present (equational) axiomatizations for several subvarieties of $mathbf{RDQDStSH_1}$. The paper concludes with some open problems for further investigation.

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