Automata, Languages, and Machines
Automata, Languages, and Machines
Automata: Theoretic Aspects of Formal Power Series
Automata: Theoretic Aspects of Formal Power Series
The Support of a Recognizable Series over a Zero-Sum Free, Commutative Semiring Is Recognizable
DLT '09 Proceedings of the 13th International Conference on Developments in Language Theory
MFCS '09 Proceedings of the 34th International Symposium on Mathematical Foundations of Computer Science 2009
On the supports of recognizable series over a field and a single letter alphabet
Information Processing Letters
Hi-index | 0.89 |
A recognizable series over the semiring of the integers is a function that maps each word over an alphabet to an integer. The support of such a series consists of all those words which are not mapped to zero. It is long known that there are recognizable series whose support is not a recognizable, but a context-free language. However, the problem of deciding whether the support of a given recognizable series is recognizable was never considered. Here we show that this problem is undecidable. The proof relies on an encoding of an instance of Post@?s correspondence problem.