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Lattices of relative colour-families and antivarieties

Aleksandr Kravchenko (2007)

Discussiones Mathematicae - General Algebra and Applications

We consider general properties of lattices of relative colour-families and antivarieties. Several results generalise the corresponding assertions about colour-families of undirected loopless graphs, see [1]. Conditions are indicated under which relative colour-families form a lattice. We prove that such a lattice is distributive. In the class of lattices of antivarieties of relation structures of finite signature, we distinguish the most complicated (universal) objects. Meet decompositions in lattices...

Lattices of Scott-closed sets

Weng Kin Ho, Dong Sheng Zhao (2009)

Commentationes Mathematicae Universitatis Carolinae

A dcpo P is continuous if and only if the lattice C ( P ) of all Scott-closed subsets of P is completely distributive. However, in the case where P is a non-continuous dcpo, little is known about the order structure of C ( P ) . In this paper, we study the order-theoretic properties of C ( P ) for general dcpo’s P . The main results are: (i) every C ( P ) is C-continuous; (ii) a complete lattice L is isomorphic to C ( P ) for a complete semilattice P if and only if L is weak-stably C-algebraic; (iii) for any two complete semilattices...

Lattices with complemented tolerance lattice

Sándor Radelecki, Dietmar Schweigert (2004)

Czechoslovak Mathematical Journal

We characterize lattices with a complemented tolerance lattice. As an application of our results we give a characterization of bounded weakly atomic modular lattices with a Boolean tolerance lattice.

Lattice-theoretically characterized classes of finite bands

Reinhard Thron, Jörg Koppitz (2003)

Archivum Mathematicum

There are investigated classes of finite bands such that their subsemigroup lattices satisfy certain lattice-theoretical properties which are related with the cardinalities of the Green’s classes of the considered bands, too. Mainly, there are given disjunctions of equations which define the classes of finite bands.

Le diagramme du treillis permutoèdre est intersection des diagrammes de deux produits directs d'ordres totaux

Claude Le Conte de Poly-Barbut (1990)

Mathématiques et Sciences Humaines

Deux codages sont utilisés sur l’ensemble des permutations ou ordres totaux sur un ensemble fini à n éléments et à chacun de ces codages est associé un produit direct d’ordres totaux. On démontre que le diagramme du treillis permutoèdre (ou ordre de Bruhat faible sur le groupe symétrique S n ) est intersection des diagrammes des deux produits directs de n - 1 ordres totaux à 2 , 3 , . . . , n éléments.

Le module dendriforme sur le groupe cyclique

Frédéric Chapoton (2008)

Annales de l’institut Fourier

La structure d’opérade anticyclique de l’opérade dendriforme donne en particulier une matrice d’ordre n agissant sur l’espace engendré par les arbres binaires plans à n feuilles. On calcule le polynôme caractéristique de cette matrice. On propose aussi une conjecture compatible pour le polynôme caractéristique de la transformation de Coxeter du poset de Tamari, qui est essentiellement une racine carrée de cette matrice.

Left and right semi-uninorms on a complete lattice

Yong Su, Zhudeng Wang, Keming Tang (2013)

Kybernetika

Uninorms are important generalizations of triangular norms and conorms, with a neutral element lying anywhere in the unit interval, and left (right) semi-uninorms are non-commutative and non-associative extensions of uninorms. In this paper, we firstly introduce the concepts of left and right semi-uninorms on a complete lattice and illustrate these notions by means of some examples. Then, we lay bare the formulas for calculating the upper and lower approximation left (right) semi-uninorms of a binary...

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