Results 21 to 30 of about 302 (48)

Closures of regular languages for profinite topologies [PDF]

, 2014
The Pin-Reutenauer algorithm gives a method, that can be viewed as a descriptive procedure, to compute the closure in the free group of a regular language with respect to the Hall topology.
A Moura, AW Anissimow, B Herwig, B Steinberg, B Steinberg, CJ Ash, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J-É Pin, J. Almeida, J. C. Costa, JC Costa, JP McCammond, K Auinger, K Auinger, K Henckell, K Henckell, K Henckell, K Numakura, L Ribes, M. Zeitoun   +29 more
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Tameness of pseudovariety joins involving R [PDF]

, 2004
2000 Mathematics Subject Classification: 20M07 (primary); 20M05, 20M35, 68Q70 (secondary).In this paper, we establish several decidability results for pseudovariety joins of the form VvW, where V is a subpseudovariety of J or the pseudovariety R.
B Herwig, B Steinberg, CJ Ash, D Albert, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Almeida, J Rhodes, J-E Pin, JC Costa, JC Costa, Jorge Almeida, José Carlos Costa, K Auinger, M Zeitoun, Marc Zeitoun, Th Coulbois   +26 more
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Factoriality and the pin-reutenauer procedure [PDF]

, 2016
We consider implicit signatures over finite semigroups determined by sets of pseudonatural numbers. We prove that, under relatively simple hypotheses on a pseudovariety V of semigroups, the finitely generated free algebra for the largest such signature ...
Almeida, Jorge, Costa, José Carlos, Zeitoun, Marc   +2 more
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Varieties of Languages in a Category

, 2015
Eilenberg's variety theorem, a centerpiece of algebraic automata theory, establishes a bijective correspondence between varieties of languages and pseudovarieties of monoids.
Adamek, Jiri, Milius, Stefan, Myers, Robert, Urbat, Henning   +3 more
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The rank of variants of nilpotent pseudovarieties

, 2020
We investigate the rank of pseudovarieties defined by several of the variants of nilpotency conditions for semigroups in the sense of Mal'cev. For several of them, we provide finite bases of pseudoidentities.
Almeida, J., Shahzamanian, M. H.
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ω-terms over finite aperiodic semigroups [PDF]

, 2008
This paper provides a characterization of pseudowords over the pseudovariety of all finite aperiodic semigroups that are given by w-terms, that is that can be obtained from the free generators using only multiplication and the w-power.
Almeida, Jorge, Costa, José Carlos, Zeitoun, Marc   +2 more
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Implicit operations on DS [PDF]

, 1991
In this work we illustrate how the study of the topological semigroups of implicit operations of a pseudovariety V can be useful to the knowledge of V.
Azevedo, Assis
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Commutative positive varieties of languages

, 2017
We study the commutative positive varieties of languages closed under various operations: shuffle, renaming and product over one-letter ...
Almeida, Jorge, Pin, Jean-Éric, Ésik, Zoltán   +2 more
core   +1 more source

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.
core   +1 more source

Formalized proof, computation, and the construction problem in algebraic geometry [PDF]

, 2004
An informal discussion of how the construction problem in algebraic geometry motivates the search for formal proof methods. Also includes a brief discussion of my own progress up to now, which concerns the formalization of category theory within a ZFC ...
Simpson, Carlos T.
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