An Algebraic Characterization of Unary Two-Way Transducers
Two-way transducers are ordinary finite two-way automata that are provided with a one-way write-only tape. They perform a word to word transformation. Unlike one-way transducers, no characterization of these objects as such exists so far except for the deterministic case. We study the other particular case where the input and output alphabets are both unary but when the transducer is not necessarily deterministic. This yields a family which extends properly the rational relations in a very natural manner. We show that deterministic two-way unary transducers are no more powerful than one-way transducers.
Unable to display preview. Download preview PDF.
- 1.Berstel, J.: Transductions and context-free languages. B. G. Teubner (1979)Google Scholar
- 2.Eilenberg, S.: Automata, Languages and Machines, vol. A. Academic Press (1974)Google Scholar
- 5.Filiot, E., Gauwin, O., Reynier, P.A., Servais, F.: From two-way to one-way finite state transducers. In: LICS, pp. 468–477 (2013)Google Scholar
- 6.Hopcroft, J.E., Ullman, J.D.: Introduction to Automata Theory, Languages and Computation. Addison-Wesley (1979)Google Scholar
- 9.Sakarovitch, J.: Elements of Automata Theory. Cambridge University Press (2009)Google Scholar