Degrees of non-monotonicity for restarting automata

Degrees of (Non)Monotonicity of RRW-Automata

We introduce and study the notion of j-monotonicity of RRand RRW -automata (special types of restarting automata without working symbols). We show that the j-monotonicity can be considered as a degree of non-context-freeness of languages recognized by RRW -automata and RR-automata. 1-monotonic RRW -automata recognize a subset of the class of context-free languages. For j > 1, the j-monotonic RR...

Restarting Automata and Variants of j-Monotonicity

In the literature various notions of (non-) monotonicity of restarting automata have been studied. Here we introduce two new variants of (non-) monotonicity for restarting automata and for two-way restarting automata: left (non-) monotonicity and right-left (non-) monotonicity. It is shown that for the various types of deterministic and nondeterministic (two-way) restarting automata without aux...

Restarting Tree Automata

Lower Bounds for Nonforgetting Restarting Automata and CD-Systems of Restarting Automata

Some lower bound results are presented that separate the language classes accepted by certain types of nonforgetting restarting automata or CD-systems of restarting automata from each other.

Lookahead Hierarchies of Restarting Automata

The restarting automaton is a special kind of the linear bounded automaton with a read/write window of fixed length. It works in cycles, reducing the length of the actual word in each cycle. We study several versions of restarting automata and we show several hierarchies of language classes recognized by them with respect to the size of the read/write-window.