All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 109 Next

Displaying 2161 – 2180 of 2555

Showing per page

The order of normalform hypersubstitutions of type (2)

Klaus Denecke, Kazem Mahdavi (2000)

Discussiones Mathematicae - General Algebra and Applications

In [2] it was proved that all hypersubstitutions of type τ = (2) which are not idempotent and are different from the hypersubstitution whichmaps the binary operation symbol f to the binary term f(y,x) haveinfinite order. In this paper we consider the order of hypersubstitutionswithin given varieties of semigroups. For the theory of hypersubstitution see [3].

The pseudovariety of semigroups of triangular matrices over a finite field

Jorge Almeida, Stuart W. Margolis, Mikhail V. Volkov (2005)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

We show that semigroups representable by triangular matrices over a fixed finite field form a decidable pseudovariety and provide a finite pseudoidentity basis for it.

The rank of a commutative semigroup

Antonio M. Cegarra, Mario Petrich (2009)

Mathematica Bohemica

The concept of rank of a commutative cancellative semigroup is extended to all commutative semigroups S by defining rank S as the supremum of cardinalities of finite independent subsets of S . Representing such a semigroup S as a semilattice Y of (archimedean) components S α , we prove that rank S is the supremum of ranks of various S α . Representing a commutative separative semigroup S as a semilattice of its (cancellative) archimedean components, the main result of the paper provides several characterizations...

Currently displaying 2161 – 2180 of 2555