We develop a theory of vector spaces spanned by orbit-finite sets. Using this theory, we give
a decision procedure for equivalence of weighted register automata, which are the common …

We consider the problems of language inclusion and language equivalence for Vector
Addition Systems with States (VASSes) with the acceptance condition defined by the set of …

We study the class of rational recursive sequences (ratrec) over the rational numbers. A
ratrec sequence is defined via a system of sequences using mutually recursive equations of …

A reactive system is a system that continuously interacts with its environment. The
environment provides an input signal, to which the system reacts with an output signal, and …

Register automata are finite automata equipped with a finite set of registers ranging over the
domain of some relational structure like $(\mathbb N;=) $ or $(\mathbb Q;<) $. Register …

Commutative images (Parikh images) are extensively studied for languages of finite
automata and context-free grammars over finite alphabets. Parikh's theorem is a well-known …

In the classical setting, the set of signals available to the machine is assumed to be finite.
However, this assumption is not realistic for modelling systems that process data from a …

We are motivated by the following question: which data languages admit an active learning
algorithm? This question was left open in previous work by the authors, and is particularly …

We are motivated by the following question: which data languages admit an active learning
algorithm? This question was left open in previous work, and is particularly challenging for …