The search session has expired. Please query the service again.

The search session has expired. Please query the service again.

The search session has expired. Please query the service again.

The search session has expired. Please query the service again.

Displaying 161 – 180 of 456

Showing per page

On low-complexity bi-infinite words and their factors

Alex Heinis (2001)

Journal de théorie des nombres de Bordeaux

In this paper we study bi-infinite words on two letters. We say that such a word has stiffness k if the number of different subwords of length n equals n + k for all n sufficiently large. The word is called k -balanced if the numbers of occurrences of the symbol a in any two subwords of the same length differ by at most k . In the present paper we give a complete description of the class of bi-infinite words of stiffness k and show that the number of subwords of length n from this class has growth order...

On minimal ideals in semigroups with respect to their subsets. I.

Imrich Abrhan (1997)

Mathematica Bohemica

In the paper, the following concept are defined: (i) a minimal left (right, two-sided) ideal with respect to a subset B of a semigroup S , (ii) a kernel with respect to a subset B of a semigroup S , and their basic properties are investigated.

On modular elements of the lattice of semigroup varieties

Boris M. Vernikov (2007)

Commentationes Mathematicae Universitatis Carolinae

A semigroup variety is called modular if it is a modular element of the lattice of all semigroup varieties. We obtain a strong necessary condition for a semigroup variety to be modular. In particular, we prove that every modular nil-variety may be given by 0-reduced identities and substitutive identities only. (An identity u = v is called substitutive if the words u and v depend on the same letters and v may be obtained from u by renaming of letters.) We completely determine all commutative modular...

Currently displaying 161 – 180 of 456