pushdown transducer; self-reproducing pushdown transduction; recursively enumerable languages
After a translation of an input string, $x$, to an output string, $y$, a self- reproducing pushdown transducer can make a self-reproducing step during which it moves $y$ to its input tape and translates it again. In this self- reproducing way, it can repeat the translation $n$-times for any $n \ge 1$. This paper demonstrates that every recursively enumerable language can be characterized by the domain of the translation obtained from a self- reproducing pushdown transducer that repeats its translation no more than three times.
 Kleijn H. C. M., Rozenberg G.: On the generative power of regular pattern grammars
. Acta Inform. 20 (1983), 391–411 MR 0732313
| Zbl 0541.68048
 Revesz G. E.: Introduction to Formal Languages. McGraw–Hill, New York 1983