The word problem for some classes of Adian inverse semigroups

We show that all of the Schützenberger complexes of an Adian inverse semigroup are finite if the Schützenberger complex of every positive word is finite. This enables us to solve the word problem for certain classes of Adian inverse semigroups (and hence for the corresponding Adian semigroups and Adian groups).     

关于一元逆半群簇的一个问题

逆半群是一种非常重要的半群,为半群代数理论的发展提供了十分重要的思想和方法.主要研究了一元逆半群簇的基底个数.利用等式逻辑证明了一元逆半群簇可由三个等式决定.     

Frucht theorem for inverse semigroups

In the paper, the problem of representing a finite inverse semigroup by partial transformations of a graph is treated. The notions of weighted graph and its weighted partial isomorphisms are introduced. The main result is that any finite inverse semigroup is isomorphic to the semigroup of weighted partial isomorphisms of a weighted graph. This assertion is a natural generalization of the Frucht theorem for groups. Translated fromMatematicheskie Zametki, Vol. 61, No. 2, pp. 246–251, February, 1997. This research was partially supported by the International Science Foundation under grant No. GSU 041049. Translated by A. I. Shtern     

Finite derivation type for semilattices of semigroups

In this paper we investigate how the combinatorial property finite derivation type (FDT) is preserved in a semilattice of semigroups. We prove that if $S= \mathcal{S}[Y,S_{\alpha}]$ is a semilattice of semigroups such that Y is finite and each S _?? (????Y) has FDT, then S has FDT. As a consequence we can show that a strong semilattice of semigroups $\mathcal{S}[Y,S_{\alpha},\lambda_{\alpha,\beta}]$ has FDT if and only if Y is finite and every semigroup S _?? (????Y) has FDT.     

Embedding inverse semigroups in coset semigroups

The setK(G) of all cosets X of a group G, modulo all subgroups of G, forms an inverse semigroup under the multiplication X*Y=smallest coset that constains XY. In this note we show that each inverse semigroup S can be embedded in some coset semigroupK(G). This follows from a result which shows that symmetric inverse semigroups can be embedded in the coset semigroups of suitable symmetric groups. We also give necessary and sufficient conditions on an inverse semigroup S in order that it should be isomorphic to someK(G). This research was supported by a grant from the National Science Foundation.     

Free inverse semigroups

This note announces a characterization of the free inverse semigroup I on a non-empty set X.     

Coverages on inverse semigroups

Semigroup Forum - First we give a definition of a coverage on an inverse semigroup that is weaker than the one given by Lawson and Lenz and that generalizes the definition of a coverage on a...     

On graph inverse semigroups

Semigroup Forum - We study the relationship between the graph inverse semigroups of two graphs when there is a directed immersion between the graphs and we provide structural information about...