23 citations · 195 across the 40 of their papers we have counts for
8 papers · 1 filter
The Finiteness Problem for Automaton Semigroups of Extended Bounded Activity
Daniele D'Angeli, Emanuele Rodaro, Jan Philipp Wächter
We extend the notion of activity for automaton semigroups and monoids introduced by Bartholdi, Godin, Klimann and Picantin to a more general setting. Their activity notion was alre…
The Freeness Problem for Automaton Semigroups
Daniele D'Angeli, Emanuele Rodaro, Jan Philipp Wächter
We show that the freeness problems for automaton semigroups and for automaton monoids are undecidable and, thereby, solve an open problem listed by Grigorchuk, Nekrashevych and Sus…
On the Orbits of Automaton Semigroups and Groups
Daniele D'Angeli, Dominik Francoeur, Emanuele Rodaro +1
We investigate the orbits of automaton semigroups and groups to obtain algorithmic and structural results, both for general automata but also for some special subclasses. First, we…
Infinite Automaton Semigroups and Groups Have Infinite Orbits
Daniele D'Angeli, Dominik Francoeur, Emanuele Rodaro +1
We show that an automaton group or semigroup is infinite if and only if it admits an -word (i. e. a right-infinite word) with an infinite orbit, which solves an open problem com…
Orbit Expandability of Automaton Semigroups and Groups
Daniele D'Angeli, Emanuele Rodaro, Jan Philipp Wächter
We introduce the notion of expandability in the context of automaton semigroups and groups: a word is k-expandable if one can append a suffix to it such that the size of the orbit…
On the Structure Theory of Partial Automaton Semigroups
Daniele D'Angeli, Emanuele Rodaro, Jan Philipp Wächter
We study automaton structures, i.e. groups, monoids and semigroups generated by an automaton, which, in this context, means a deterministic finite-state letter-to-letter transducer…