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arXiv · 1105.4725

On the Finiteness Problem for Automaton (Semi)groups

Ali Akhavi·Ines Klimann·Sylvain Lombardy·Jean Mairesse·Matthieu Picantin
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Abstract

This paper addresses a decision problem highlighted by Grigorchuk, Nekrashevich, and Sushchanskii, namely the finiteness problem for automaton (semi)groups. For semigroups, we give an effective sufficient but not necessary condition for finiteness and, for groups, an effective necessary but not sufficient condition. The efficiency of the new criteria is demonstrated by testing all Mealy automata with small stateset and alphabet. Finally, for groups, we provide a necessary and sufficient condition that does not directly lead to a decision procedure.

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Ali Akhavi, Ines Klimann, Sylvain Lombardy, Jean Mairesse, Matthieu Picantin. 2011-05-24. On the Finiteness Problem for Automaton (Semi)groups. https://doi.org/10.1142/s021819671250052x

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