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arXiv · 1405.2892

New Results on the Minimum Amount of Useful Space

Zuzana Bednárová·Viliam Geffert·Klaus Reinhardt·Abuzer Yakaryilmaz
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Abstract

We present several new results on minimal space requirements to recognize a nonregular language: (i) realtime nondeterministic Turing machines can recognize a nonregular unary language within weak $\log\log n$ space, (ii) $\log\log n$ is a tight space lower bound for accepting general nonregular languages on weak realtime pushdown automata, (iii) there exist unary nonregular languages accepted by realtime alternating one-counter automata within weak $\log n$ space, (iv) there exist nonregular languages accepted by two-way deterministic pushdown automata within strong $\log\log n$ space, and, (v) there exist unary nonregular languages accepted by two-way one-counter automata using quantum and classical states with middle $\log n$ space and bounded error.

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Zuzana Bednárová, Viliam Geffert, Klaus Reinhardt, Abuzer Yakaryilmaz. 2014-05-12. New Results on the Minimum Amount of Useful Space. https://arxiv.org/abs/1405.2892

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