Results 41 to 50 of about 775 (107)

On Relative Principal Congruences in Term Quasivarieties

Studia Logica, 2022
Hernán J San Martín, San Martín Hernán Javier   +1 more
exaly   +3 more sources

Categorial quasivarieties

Algebra and Logic, 1972
A I Abakumov, E A Palyutin, Palyutin E A
exaly   +2 more sources

Omission and Bases for Quasivarieties

2018
In this section we show that if \(\mathcal{K}\) is a locally finite quasivariety of finite type, T is a finite algebra in \(\mathcal{K}\), and α ≻ Δ in \(\mathop{\mathrm{Con}}\nolimits _{\mathcal{K}}\,\mathbf{T}\), then the quasivariety \(\langle \varepsilon _{\mathbf{T},\alpha }\rangle\) consists of all algebras in \(\mathcal{K}\) that omit a finite ...
Jennifer Hyndman, J. B. Nation
openaire   +2 more sources

Quasivarieties of p-Algebras: Some New Results

Studia Logica
We investigate quasivarieties of (distributive) p-algebras. We sharpen some previous results, give a better picture of the subquasivariety lattice, and prove that quasivarieties generated by free p-algebras belong to a rather small quasivariety ...
Tomasz Kowalski, Katarzyna Słomczyńska   +1 more
exaly   +2 more sources

QUASIVARIETIES OF IDEMPOTENT SEMIGROUPS

International Journal of Algebra and Computation, 2003
It is proved that the lattice L(Bd) of quasivarieties contained in the variety Bdof idempotent semigroups contains an isomorphic copy of the ideal lattice of a free lattice on ω free generators. This result shows that a problem of Petrich [19], which calls for a description of L(Bd), is much more complex than originally expected.
M. E. Adams, Wieslaw Dziobiak
openaire   +2 more sources

Semigroup quasivarieties: Two lattices and a reopened problem

International journal of algebra and computation, 2021
We determine all quasivarieties of aperiodic semigroups that are contained in some residually finite variety. This endeavor was initially motivated by a problem in natural dualities, but our work here also serves as a partial correction to an error found
Timothy J. Koussas
semanticscholar   +1 more source

On quasivarieties of axiomatic rank 3 of torsion-free nilpotent groups

Siberian Mathematical Journal, 2017
A I Budkin, Budkin A I
exaly   +3 more sources

ASSERTIONALLY EQUIVALENT QUASIVARIETIES

International Journal of Algebra and Computation, 2008
A translation in an algebraic signature is a finite conjunction of equations in one variable. On a quasivariety K, a translation τ naturally induces a deductive system, called the τ-assertional logic of K. Two quasivarieties are τ-assertionally equivalent if they have the same τ-assertional logic. This paper is a study of assertional equivalence.
Willem J. Blok, James G. Raftery 0001
openaire   +1 more source

Сharacterization of distributive lattices of quasivarieties of unars

, 2021
Let Lq(M) denote the lattice of all subquasivarieties of the quasivariety M under inclusion. There is a strong correlation between the properties of the lattice Lq(M) and algebraic systems from M. A. I.
V. Kartashov, A. Kartashova
semanticscholar   +1 more source

Levi classes of quasivarieties of 2-nilpotent groups

Mathematics and Theoretical Computer Science
The Levi class L(M) generated by the class of groups M is the class of all groups in which the normal closure of each cyclic subgroup belongs to M.Let p be a prime number, p ̸= 2, s be a natural number, s ≥ 2, and s > 2 for p = 3; Hps be a free group of ...
S. M. Shakhova
semanticscholar   +1 more source