Results 21 to 30 of about 104 (40)
Free three-valued Closure Lukasiewicz Algebras [PDF]
, 2007 In this paper, the structure of finitely generated free objects in the variety of three-valued closure Lukasiewicz algebras is determined. We describe their indecomposable factors and we give their cardinality.Fil: Abad, Manuel.
Abad, Manuel +3 more
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Modular and lower-modular elements of lattices of semigroup varieties [PDF]
, 2010 The paper contains three main results. First, we show that if a commutative semigroup variety is a modular element of the lattice Com of all commutative semigroup varieties then it is either the variety COM of all commutative semigroups or a nil-variety ...
L. N. Shevrin, V. Yu. Shaprynskǐi
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A family of varieties of pseudosemilattices
, 2013 In [3], a basis of identities {u_n = v_n | n\geq 2} for the variety SPS of all strict pseudosemilattices was determined. Each one of these identities u_n = v_n has a peculiar 2-content D_n.
Oliveira, Luis
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Distributive Laws in Residuated Binars [PDF]
, 2019 In residuated binars there are six non-obvious distributivity identities of ⋅,/,∖ over ∧,∨. We show that in residuated binars with distributive lattice reducts there are some dependencies among these identities; specifically, there are six pairs of ...
Fussner, Wesley, Jipsen, Peter
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Combinatorial Rees–Sushkevich Varieties That Are Cross, Finitely Generated, Or Small [PDF]
, 2010 A variety is said to be a Rees–Sushkevich variety if it is contained in a periodic variety generated by 0-simple semigroups. Recently, all combinatorial Rees–Sushkevich varieties have been shown to be finitely based.
Lee, Edmond W. H.
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Implicative algebras and Heyting algebras can be residuated lattices [PDF]
, 2017 The commutative residuated lattices were first introduced by M. Ward and R.P. Dilworth as generalization of ideal lattices of rings. Complete studies on residuated lattices were developed by H. Ono, T. Kowalski, P. Jipsen and C. Tsinakis.
Merdach, Huda H., Samir, Basim
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Varieties of Monoids with Complex Lattices of Subvarieties [PDF]
, 2020 A variety is finitely universal if its lattice of subvarieties contains an isomorphic copy of every finite lattice. Examples of finitely universal varieties of semigroups have been available since the early 1970s, but it is unknown if there exists a ...
Gusev, Sergey V., Lee, Edmond W. H.
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Semiring identities in the semigroup $B_0$
, 2023 The semigroup $B_0$ is the only, up to isomorphism, 4-element subsemigroup of the 5-element Brandt semigroup $B_2$. Being an inverse semigroup, the semigroup $B_2$ can naturally be considered an additively idempotent semiring and $B_0$ is its subsemiring.
Shaprynskiǐ, Vyacheslav Yu.
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Lower-modular elements of the lattice of semigroup varieties. III
, 2010 We completely determine all lower-modular elements of the lattice of all semigroup varieties. As a corollary, we show that a lower-modular element of this lattice is modular.Comment: 10 pages, 1 ...
Shaprynskii, V. Yu., Vernikov, B. M.
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The Burnside ai-semiring variety defined by $x^n\approx x$
, 2022 Let ${\bf Sr}(n, 1)$ denote the ai-semiring variety defined by the identity $x^n\approx x$, where $n>1$. We characterize all subdirectly irreducible members of a semisimple subvariety of ${\bf Sr}(n, 1)$.
Ren, Miaomiao +2 more
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