Sequential monotonicity for restarting automata

Jurdziński, Tomasz; Otto, Friedrich

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 41 (2007) no. 2, pp. 157-175.

As already 2-monotone R-automata accept NP-complete languages, we introduce a restricted variant of $j$-monotonicity for restarting automata, called sequential $j$-monotonicity. For restarting automata without auxiliary symbols, this restricted variant still yields infinite hierarchies. However, for restarting automata with auxiliary symbols, all degrees of sequential monotonicity collapse to the first level, implying that RLWW-automata that are sequentially monotone of degree $j$ for any $j\ge 1$ only accept context-free languages.

Classification : 68Q45
Mots clés : restarting automaton, sequential monotonicity, hierarchies

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