Results 1 to 10 of about 129 (63)

Some non-standard quasivarieties of lattices [PDF]

Қарағанды университетінің хабаршысы. Математика сериясы, 2023
The questions of the standardness of quasivarieties have been investigated by many authors. The problem "Which finite lattices generate a standard topological prevariety?" was suggested by D.M. Clark, B.A. Davey, M.G. Jackson and J.G.
S.M. Lutsak, A.O. Basheyeva, A.M. Asanbekov, O.A. Voronina   +3 more
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Structure of Quasivariety Lattices. IV. Nonstandard Quasivarieties

Siberian Mathematical Journal, 2021
Let \(\sigma\) be a finite signature and let \(\mathcal M\) be a quasivariety of signature \(\sigma\). According to Definition 4 of the paper, a class \(\mathcal A=\{\mathbb A_X\;|\;X\in {\mathcal P}_{\textrm{fin}}(\omega)\}\subseteq {\mathcal M}\) of finite \(\sigma\)-structures is called a \textit{finite \(B\)-class} with respect to \(\mathcal M\) if
Kravchenko, A. V., Nurakunov, A. M., Schwidefsky, M. V.   +2 more
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Finite Lattices Generating Not Finitely–Based and Nonstandard Quasivarieties [PDF]

Journal of Mathematics
There are two well-known and closely related problems in lattice theory: Which finite lattices generate finitely-based quasivarieties? and Which finite lattices generate standard quasivarieties?
M. A. Arapbay, A. O. Basheyeva, S. M. Lutsak   +2 more
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Finite atomistic lattices that can be represented as lattices of quasivarieties [PDF]

Fundamenta Mathematicae, 1993
Summary: We prove that a finite atomistic lattice can be represented as a lattice of quasivarieties if and only if it is isomorphic to the lattice of all subsemilattices of a finite semilattice. This settles a conjecture that appeared in the context of an earlier paper by the third author and \textit{V. I.
Adaricheva, K. V., Dziobiak, W., Gorbunov, V. A.   +2 more
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Сharacterization of distributive lattices of quasivarieties of unars

Chebyshevskii sbornik, 2021
Vladimir Konstantinovich Kartashov, Anna Vladimirovna Kartashova   +1 more
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On quasi-identities of finite modular lattices. II [PDF]

Қарағанды университетінің хабаршысы. Математика сериясы, 2023
The existence of a finite identity basis for any finite lattice was established by R. McKenzie in 1970, but the analogous statement for quasi-identities is incorrect.
A.O. Basheyeva, S.M. Lutsak
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The complexity of quasivariety lattices of unary algebras

BULLETIN OF THE KARAGANDA UNIVERSITY-MATHEMATICS, 2017
S. M. Lutsak
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The inconsistency predicate on De Morgan lattices

Acta Universitatis Carolinae: Philosophica et Historica, 2017
We consider expansions of De Morgan lattices by an additional unary predicate interpreted in each De Morgan lattice by the ideal generated by all elements of the form a ∧ −a, and describe the finite lattice of strict universal Horn classes of such ...
Adam Přenosil
doaj   +1 more source

Lattices of Quasivarieties of 3-Element Algebras

Journal of Algebra, 1994
This well-written paper contains many interesting results from the structure of lattices of subquasivarieties. A quasivariety is any class of similar algebraic structures that is closed under isomorphisms, substructures, direct products, and ultraproducts.
Adams, M.E., Dziobiak, W.
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On the complexity of quasivariety lattices

Sibirskie Elektronnye Matematicheskie Izvestiya, 2017
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +1 more source