A topological approach to transductions (2008)
This paper is a contribution to the mathematical foundations of the theory of automata. We give a topological characterization of the transductions τ from a monoid M into a monoid N, such that if R...
On the rational subset problem for groups (2008)
Mark Kambites, Pedro V. Silva, Benjamin Steinberg, Mims Eprint, Mark Kambites A, ...
We use language theory to study the rational subset problem for groups and monoids. We show that the decidability of this problem is preserved under graph of groups constructions with finite edge...
A topological approach to transductions (2008)
This paper is a contribution to the mathematical foundations of the theory of automata. We give a topological characterization of the transductions τ from a monoid M into a monoid N, such that if R...
A topological approach to transductions (2008)
1 Introduction This paper is a contribution to the mathematical foundations of automata the-ory. We are mostly interested in the study of transductions o / from a monoid M into another monoid N such...
51. A Mahler's theorem for functions from words to integers (2008)
Pin, Jean-Éric, Silva, Pedro V.
In this paper, we prove an extension of Mahler's theorem, a celebrated result of $p$-adic analysis. Mahler's original result states that a function from $N$ to $Z$ is uniformly continuous for the...
Pedro V. Silva, Centro De Matematica, Faculdade De Ci^encias
It is proved to be decidable, for any given nite subset F of X and mapping ':
Recognizable subsets of a group: nite extensions and the abelian case (2007)
It is proved that for rational free abelian group languages recognizability is decidable and the corresponding syntactic congruences are also decidable. Other results focus the problem of relating...
Periodicity vectors for labelled trees (2007)
Antonio Restivo, Pedro V. Silva
The concept of periodicity vector is introduced in the context of labelled trees, and some new periodicity theorems are obtained. These results constitute generalizations of the classical Fine and...
On the lattice of prex codes (2007)
Antonio Restivo, Pedro V. Silva
The natural correspondence between prex codes and trees is explored, generalizing the results obtained in [6] for the lattice of nite trees under division and the lattice of nite maximal prex codes....
A Mahler’s theorem for functions from words to integers ∗ (2007)
In this paper, we prove an extension of Mahler’s theorem, a celebrated result of p-adic analysis. Mahler’s original result states that a function from N to Z is uniformly continuous for the...
On the rational subset problem for groups (2006)
Kambites, Mark, Silva, Pedro V., Steinberg, Benjamin
We use language theory to study the rational subset problem for groups and monoids. We show that the decidability of this problem is preserved under graph of groups constructions with finite edge...
The spectra of lamplighter groups and Cayley machines (2006)
Kambites, Mark, Silva, Pedro V., Steinberg, Benjamin
We calculate the spectra and spectral measures associated to random walks on restricted wreath products G wr $$\mathbb{Z}$$, with G a finite group, by calculating the Kesten—von Neumann—Serre...
On the rational subset problem for groups (2006)
Kambites, Mark, Silva, Pedro V., Steinberg, Benjamin
We use language theory to study the rational subset problem for groups and monoids. We show that the decidability of this problem is preserved under graph of groups constructions with finite edge...
The Spectra of Lamplighter Groups and Cayley Machines (2004)
Kambites, Mark, Silva, Pedro V., Steinberg, Benjamin
We calculate the spectra and spectral measures associated to random walks on restricted wreath products of finite groups with the infinite cyclic group, by calculating the Kesten-von Neumann-Serre...
A Geometric Characterization of Automatic Monoids (2004)
Silva, Pedro V., Steinberg, Benjamin
It is well known that automatic groups can be characterized using geometric properties of their Cayley graphs. Along the same line of thought, we provide a geometric characterization of automatic...
An Application of First-Order Logic to the Study of Recognizable Languages (2003)
A variation of first-order logic with variables for exponents is developed to solve some problems in the setting of recognizable languages on the free monoid, accommodating operators such as product,...
A geometric characterization of automatic monoids (2001)
Pedro V. Silva, Benjamin Steinberg
It is well known that automatic groups can be characterized using geometric properties of their Cayley graphs. Along the same line of thought, we provide a geometric characterization of automatic...
Free group languages: rational versus recognizable (2001)
We provide alternative proofs and algorithms for results proved by Geraud Senizergues on rational and recognizable free group languages. We consider two dierent approaches to the basic problem of...
Extensions and Submonoids of Automatic Monoids (2000)
Pedro V. Silva, Benjamin Steinberg
In this paper, submonoids and extensions of automatic and p-automatic monoids are studied. The concept of a p-automatic monoid is a variant on the usual concept of an automatic monoid designed to...
A Geometric Characterization of Automatic Monoids (2000)
Pedro V. Silva, Benjamin Steinberg
It is well-known that automatic groups can be characterized using geometric properties of their Cayley graphs. Along the same line of thought, we provide a geometric characterization of automatic...
SC-Hyperdecidability Of R (1997)
A class TC(X) of X-graphs is introduced, and an algorithmic property of labellings of finite strongly connected graphs by rational languages is shown to be decidable. This property, named as...
On the Hyperdecidability of Semidirect Products of Pseudovarieties (1997)
The notion of hyperdecidability has been introduced as a tool which is particularly suited for granting decidability of semidirect products. It is shown in this paper that the semidirect product of...
Almeida, Jorge, Gomes, Gracinda M. S, Silva, Pedro V
"The Conference "Semigroups, Automata and Languages" was held at the Faculty of Sciences of the University of Porto on June 20-24, 1994"