Results 11 to 20 of about 198 (35)
All Maximal Completely Regular Submonoids of HypG(2)
Discussiones Mathematicae - General Algebra and Applications, 2017 In this paper we consider mappings σ which map the binary operation symbol f to the term σ (f) which do not necessarily preserve the arity. These mapping are called generalized hypersubstitutions of type τ = (2) and we denote the set of all these ...
Kunama Pornpimol, Leeratanavalee Sorasak
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On the ascending and descending chain conditions in the lattice of monoid varieties [PDF]
, 2019 In this work we consider monoids as algebras with an associative binary operation and the nullary operation that fixes the identity element. We found an example of two varieties of monoids with finite subvariety lattices such that their join covers one ...
Gusev, S. V.
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On the power pseudovariety $\mathbf{PCS}$ [PDF]
, 2012 Some new semantic and syntactic characterizations of the members of the power pseudovariety $\mathbf{PCS}$ are obtained. This leads in particular to new algorithms for deciding membership in $\mathbf{PCS}$
Auinger, K.
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A new example of a limit variety of monoids [PDF]
, 2019 A variety of universal algebras is called limit if it is non-finitely based but all its proper subvarieties are finitely based. Until recently, only two explicit examples of limit varieties of monoids, constructed by Jackson, were known.
Gusev, S. V.
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The omega-inequality problem for concatenation hierarchies of star-free languages [PDF]
, 2017 The problem considered in this paper is whether an inequality of omega-terms is valid in a given level of a concatenation hierarchy of star-free languages.
Almeida, J., Klíma, O., Kunc, M.
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Tolerances as images of congruences in varieties defined by linear identities
, 2012 An identity s=t is linear if each variable occurs at most once in each of the terms s and t. Let T be a tolerance relation of an algebra A in a variety defined by a set of linear identities.
Chajda, Ivan +3 more
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Equidivisible pseudovarieties of semigroups [PDF]
, 2016 We give a complete characterization of pseudovarieties of semigroups whose finitely generated relatively free profinite semigroups are equidivisible. Besides the pseudovarieties of completely simple semigroups, they are precisely the pseudovarieties that
Almeida, Jorge, Costa, Alfredo
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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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On a problem of M. Kambites regarding abundant semigroups [PDF]
, 2011 A semigroup is regular if it contains at least one idempotent in each -class and in each L-class. A regular semigroup is inverse if it satisfies either of the following equivalent conditions: (i) there is a unique idempotent in each -class and in each L ...
Araújo, João, Kinyon, Michael
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HeliyonThe major point of proposed work is to study optimistic multi-granulation roughness of intuitionistic fuzzy ideals by using soft relations that is free from all the complications that challenged by many researchers.
Shahida Bashir +6 more
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