Results 1 to 10 of about 138 (31)

Some remarks on connectors and groupoids in Goursat categories [PDF]

Logical Methods in Computer Science, 2017
We prove that connectors are stable under quotients in any (regular) Goursat category. As a consequence, the category $\mathsf{Conn}(\mathbb{C})$ of connectors in $\mathbb{C}$ is a Goursat category whenever $\mathbb C$ is.
Marino Gran, Diana Rodelo, Idriss Tchoffo Nguefeu   +2 more
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Varieties whose tolerances are homomorphic images of their congruences [PDF]

, 2012
The homomorphic image of a congruence is always a tolerance (relation) but, within a given variety, a tolerance is not necessarily obtained this way. By a Maltsev-like condition, we characterize varieties whose tolerances are homomorphic images of their ...
Czedli, Gabor, Kiss, Emil W.
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All Linear-Solid Varieties of Semirings

Discussiones Mathematicae - General Algebra and Applications, 2019
A variety of semirings is said to be solid if each of its identities is satisfied as hyperidentity. There are precisely four solid varieties of semirings.
Hounnon Hippolyte, Denecke Klaus
doaj   +1 more source

On some varieties of ai-semirings satisfying xp+1 ≈ x

Open Mathematics, 2018
The aim of this paper is to study the lattice of subvarieties of the ai-semiring variety defined by the additional ...
Wang Aifa, Shao Yong
doaj   +1 more source

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, Changphas Thawhat   +1 more
doaj   +1 more source

A method for finding new sets of axioms for classes of semigroups [PDF]

, 2012
We introduce a general technique for finding sets of axioms for a given class of semigroups. To illustrate the technique, we provide new sets of defining axioms for groups of exponent n, bands, and ...
A. Rezus, B. Sobociński, B.H. Neumann, C. Hollings, C.A. Meredith, C.A. Meredith, C.A. Meredith, C.A. Meredith, E.V. Huntington, E.V. Huntington, G. Higman, H.M. Sheffer, J. Araújo, J. Araújo, J. Araújo, J. Hart, J. Konieczny, J. Łukasiewicz, J.A. Kalman, J.G. Peterson, J.M. Howie, Janusz Konieczny, João Araújo, K. Kunen, K. Kunen, L. Wos, L. Wos, M. Sholander, M.K. Kinyon, P.M. Neumann, R. Croisot, R. Padmanabhan, S. Winker, T.W. Scharle, V. Tasić, W. McCune, W. McCune, W. McCune, W. McCune, W. McCune, W. McCune, W. McCune   +41 more
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Protoadditive functors, derived torsion theories and homology [PDF]

, 2011
Protoadditive functors are designed to replace additive functors in a non-abelian setting. Their properties are studied, in particular in relationship with torsion theories, Galois theory, homology and factorisation systems.
Everaert, Tomas, Gran, Marino
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On a variety of commutative multiplicatively idempotent semirings

, 2016
We prove that the variety V of commutative multiplicatively idempotent semirings satisfying x + y + xyz = x + y is generated by single semirings. Moreover, we describe a normal form system for terms in V and we show that the word problem in V is solvable.
Chajda, Ivan, Länger, Helmut
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The dimension of a variety

, 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, On February, Workshop Aaa   +2 more
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a review of A class of exactness properties characterized via left Kan extensions by Jacqmin, Pierre-Alain [PDF]

, 2021
review ...
Hirokazu Nishimura
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