Results 41 to 50 of about 20,804 (234)
Monoid rings that are firs [PDF]
, 1990 It is well-known that the monoid ring of the free product of a free group and a free monoid over a skew field is a fir.
Pitarch, A.
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Perfect congruences on a free monoid [PDF]
Proceedings of the American Mathematical Society, 1987 A congruence \(\rho\) on a monoid M is said to be ''perfect'' if the product of any two \(\rho\)-classes, considered as subsets of M, is a full \(\rho\)- class. The authors investigate the family \({\mathcal P}{\mathcal C}(X^*)\) of perfect congruences on the free monoid \(X^*\) on the alphabet X. They show that \(\rho\) is perfect if and only if it is
Petrich, Mario, Reis, C. M.
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Rationality, irrationality, and Wilf equivalence in generalized factor order [PDF]
Discrete Mathematics & Theoretical Computer Science, 2009 Let $P$ be a partially ordered set and consider the free monoid $P^{\ast}$ of all words over $P$. If $w,w' \in P^{\ast}$ then $w'$ is a factor of $w$ if there are words $u,v$ with $w=uw'v$. Define generalized factor order on $P^{\ast}$ by letting $u \leq
Sergey Kitaev +3 more
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About Applications of Distances on Monoids of Strings [PDF]
Computer Science Journal of Moldova, 2016 In this article we show that there are invariant distances on the monoid $L(A)$ of all strings closely related to Levenshtein's distance. We will use a distinct definition of the distance on $L(A)$, based on the Markov -– Graev method, proposed by ...
Mitrofan Choban, Ivan Budanaev
doaj
Structure and enumeration of $(3+1)$-free posets (extended abstract) [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 A poset is $(3+1)$-free if it does not contain the disjoint union of chains of length 3 and 1 as an induced subposet. These posets are the subject of the $(3+1)$-free conjecture of Stanley and Stembridge.
Mathieu Guay-Paquet +2 more
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On subtrees of the representation tree in rational base numeration systems [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 Every rational number p/q defines a rational base numeration system in which every integer has a unique finite representation, up to leading zeroes. This work is a contribution to the study of the set of the representations of integers.
Shigeki Akiyama +2 more
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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
Hartmann, Miklos, Gould, Victoria
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The primitive ideals of some \'etale groupoid C*-algebras [PDF]
, 2015 Consider the Deaconu-Renault groupoid of an action of a finitely generated free abelian monoid by local homeomorphisms of a locally compact Hausdorff space. We catalogue the primitive ideals of the associated groupoid C*-algebra.
Sims, Aidan, Williams, Dana P.
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Every finite system of T1 uniformities comes from a single distance structure
Applied General Topology, 2002 Using the general notion of distance function introduced in an earlier paper, a construction of the finest distance structure which induces a given quasi-uniformity is given.
Jobst Heitzig
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Congruences on free monoids and submonoids of polycyclic monoids [PDF]
Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics, 1993 AbstractWe establish a one-to-one “group-like” correspondence between congruences on a free monoid X* and so-called positively self-conjugate inverse submonoids of the polycyclic monoid P(X). This enables us to translate many concepts in semigroup theory into the language of inverse semigroups.
Meakin, John, Sapir, Mark
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