Results 11 to 20 of about 4,202,174 (239)
Infix congruences on a free monoid [PDF]
Transactions of the American Mathematical Society, 1989 A subset T of the free monoid \(X^*\) on a finite alphabet X is said to be an infix code if u,xuy\(\in T\) \(\Rightarrow\) \(xy=1\). An infix congruence is a congruence on \(X^*\) whose classes are infix codes; if these classes are also finite, the congruence is said to be f- disjunctive.
C. Reis
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On a factorisation of free monoids [PDF]
Proceedings of the American Mathematical Society, 1965 A property is given which relates two results of Spitzer [6]; it also relates two results of Chen, Fox and Lyndon [1]; the same remark applies to work of Meyer-Wunderli [5] and M. Hall [3] and to its generalisation by Lazard [4]. These connections are indicated more fully below.
M. P. Schützenberger
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Disjunctive Languages On a Free Monoid
Information and Control, 1977 A language A on a free monoid X⩽* generated by X is called a disjunctive language if the principal congruence determined by A is the identity. In this paper we show that if X contains only one letter then the disjunctive languages are exactly the nonregular languages.
H. Shyr
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Coherency, free inverse monoids and free left ample monoids
, 2015 A monoid $S$ is right coherent if every finitely generated subact of every finitely presented right $S$-act is finitely presented. The corresponding notion for a ring $R$ states that every finitely generated submodule of every finitely presented right $R$-module is finitely presented. For monoids (and rings) right coherency is a finitary property which
Miklós Hartmann, Victoria Gould
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Theoretical Computer Science, 1994 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
J. Anderson
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On metrizability of the free monoids
Discrete Mathematics, 1976 AbstractA complete solution is given of the problem of S. Marcus concerning the construction of a “better” distance in the free monoids from the viewpoint of measuring the difference of contextual behaviour with respect to a given language.
Cristian S. Calude
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Free Monoids are Coherent [PDF]
Proceedings of the Edinburgh Mathematical Society, 2016 AbstractA monoid S is said to be right coherent if every finitely generated subact of every finitely presented right S-act is finitely presented. Left coherency is defined dually and S is coherent if it is both right and left coherent. These notions are analogous to those for a ring R (where, of course, S-acts are replaced by R-modules).
Gould, Victoria +2 more
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Free inverse monoids are not ${\protect \rm FP}_2$
Comptes Rendus. Mathématique, 2021 We give a topological proof that a free inverse monoid on one or more generators is neither of type left-$\mathrm{FP}_2$ nor right-$\mathrm{FP}_2$. This strengthens a classical result of Schein that such monoids are not finitely presented as monoids.
Gray, Robert D., Steinberg, Benjamin
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Theoretical Computer Science, 1982 AbstractDominoes over a free monoid and operations on them are introduced. Related algebraic systems and their applications to decidability problems about morphisms on free monoids are studied. A new simple algorithm for testing DOL sequence equivalence is presented.
K. Culík, T. Harju
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