Results 11 to 20 of about 104 (40)
, 2016 In a paper published in 2012, the second author extended the well-known fact that Boolean algebras can be defined using only implication and a constant, to De Morgan algebras-this result led him to introduce, and investigate (in the same paper), the ...
Cornejo, Juan M. +1 more
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The Clone of K*(n, r)-Full Terms
Discussiones Mathematicae - General Algebra and Applications, 2019 Let τn be a type of algebras in which all operation symbols have arity n, for a fixed n ≥ 1. For 0 < r ≤ n, this paper introduces a special kind of n-ary terms of type τn called K*(n, r)-full terms. The set of all K*(n, r)-full terms of type τn is closed
Wattanatripop Khwancheewa +1 more
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Cancellable elements of the lattices of varieties of semigroups and epigroups [PDF]
, 2019 We completely determine all semigroup [epigroup] varieties that are cancellable elements of the lattice of all semigroup [respectively epigroup] varieties.Comment: 17 pages, 3 figures. Compared with the previous version, we add Corollary 1.4 and Figure
Shaprynskii, V. Yu. +2 more
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Cancellable elements in the lattice of overcommutative semigroup varieties [PDF]
, 2020 We completely determine all cancellable elements in the lattice OC of overcommutative semigroup varieties. In particular, we prove that an overcommutative semigroup variety is a cancellable element of the lattice OC if and only if it is a neutral element
Shaprynskii, Vyacheslav Yu. +1 more
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Special elements of the lattice of epigroup varieties [PDF]
, 2016 We study special elements of eight types (namely, neutral, standard, costandard, distributive, codistributive, modular, lower-modular and upper-modular elements) in the lattice EPI of all epigroup varieties.
Shaprynskii, V. Yu. +2 more
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On the lattice of overcommutative varieties of monoids
, 2017 It is unknown so far, whether the lattice of all varieties of monoids satisfies some non-trivial identity. The objective of this note is to give the negative answer to this question. Namely, we prove that any finite lattice is a homomorphic image of some
Gusev, S. V.
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Chain varieties of monoids [PDF]
, 2018 A variety of universal algebras is called a chain variety if its subvariety lattice is a chain. Non-group chain varieties of semigroups were completely classified by Sukhanov in 1982.
Gusev, Sergey V., Vernikov, Boris M.
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On the Complete Join of Permutative Combinatorial Rees–Sushkevich Varieties [PDF]
, 2007 A semigroup variety is a Rees–Sushkevich variety if it is contained in a periodic variety generated by 0-simple semigroups. The collection of all permutative combinatorial Rees–Sushkevich varieties constitutes an incomplete lattice that does not contain ...
Lee, Edmond W. H.
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, 2006 We invent the notion of a {\it dimension of a variety} $V$ as the cardinality of all its proper {\it derived} subvarieties (of the same type). The dimensions of varieties of lattices, varieties of regular bands and other general algebraic structures are ...
Cya In B¸edlewo +2 more
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Cancellable elements of the lattice of epigroup varieties [PDF]
, 2018 We completely determine all commutative epigroup varieties that are cancellable elements of the lattice EPI of all epigroup varieties. In particular, we verify that a commutative epigroup variety is a cancellable element of the lattice EPI if and only if
Skokov, Dmitry V.
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