Title
On the structure theory of partial automaton semigroups
Abstract
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. Instead of considering only complete automata, we specifically investigate semigroups generated by partial automata. First, we show that the class of semigroups generated by partial automata coincides with the class of semigroups generated by complete automata if and only if the latter class is closed under removing a previously adjoined zero, which is an open problem in (complete) automaton semigroup theory stated by Cain. Then, we show that no semidirect product (and, thus, also no direct product) of an arbitrary semigroup with a (non-trivial) subsemigroup of the free monogenic semigroup is an automaton semigroup. Finally, we concentrate on inverse semigroups generated by invertible but partial automata, which we call automaton-inverse semigroups, and show that any inverse automaton semigroup can be generated by such an automaton (showing that automaton-inverse semigroups and inverse automaton semigroups coincide).
Year
DOI
Venue
2018
10.1007/s00233-020-10114-5
SEMIGROUP FORUM
Keywords
DocType
Volume
Automaton semigroup,Partial automaton,Inverse semigroup,Preston-Vagner theorem
Journal
101.0
Issue
ISSN
Citations 
1
0037-1912
0
PageRank 
References 
Authors
0.34
3
3
Name
Order
Citations
PageRank
Daniele D'Angeli1297.01
Emanuele Rodaro25515.63
Jan Philipp Wächter333.57