Results 21 to 30 of about 775 (107)

On Jonsson varieties and quasivarieties

Herald of Tver State University. Series: Applied Mathematics, 2022
В работах некоторых авторов было введено понятие йонсоновского многообразия и квазимногообразия и для таких классов алгебраических систем доказаны разного рода утверждения.
Сергей Михайлович Дудаков
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On some properties of quasivarieties generated by specific finite modular lattices

BULLETIN of the L.N. Gumilyov Eurasian National University. MATHEMATICS.COMPUTER SCIENCE. MECHANICS Series, 2022
A finite algebra A with discrete topology generates a topological quasivarietyconsisting of all topologically closed subalgebras of non-zero direct powers of A endowed withthe product topology.
S. Lutsak, O. Voronina
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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
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Singly generated quasivarieties and residuated structures [PDF]

Mathematical Logic Quarterly, 2019
A quasivariety K of algebras has the joint embedding property (JEP) if and only if it is generated by a single algebra A. It is structurally complete if and only if the free ℵ0‐generated algebra in K can serve as A.
T. Moraschini, J. Raftery, J. J. Wannenburg   +2 more
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Criterion for a formula-definable quasivariety

Қарағанды университетінің хабаршысы. Математика сериясы
In this paper, we study classes of models of a first-order language L with a countable signature σ. For a model A, let Th(A) denote the set of all sentences of L that are true in A, called the elementary type of A.
M.I. Bekenov, A. Mamyraly, A. Kassatova, A. Kabidenov   +3 more
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How to Sketch Quasivarieties

Journal of Algebra, 1996
The author describes a class of sketches, ``separated limit sketches'', such that quasivarieties of finitary algebras are precisely the categories sketchable by separated finite-limit sketches. This result has an extension with ``finitary'' replaced by a cardinal parameter.
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Properties of semigroups of elementary types of model classes

Қарағанды университетінің хабаршысы. Математика сериясы
The study of classes of first-order countable language models and their properties is an important direction in model theory. Of particular interest are axiomatizable classes of models (varieties, quasivarieties, finitely axiomatizable classes ...
A. Kabidenov, A. Kassatova, M. Bekenov, A. Mamyraly   +3 more
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Localizations of varieties and quasivarieties

Journal of Pure and Applied Algebra, 2000
It is well known that varieties (= monadic categories over sets) are nothing but exact categories having a regular projective regular generator with copowers. It is also well known that quasivarieties (= regular epireflective full subcategories of varieties) are nothing but regular categories having coequalizers of equivalence relations and a regular ...
PEDICCHIO, MARIA CRISTINA, J. ROSICKY
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Convex congruences. [PDF]

Soft comput, 2017
Chajda I, Länger H.
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Counting quasivarieties of equivalential algebras [PDF]

Reports Math. Log., 2000
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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