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arXiv · 1710.00213

Two-way Two-tape Automata

Olivier Carton·Léo Exibard·Olivier Serre
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Abstract

In this article we consider two-way two-tape (alternating) automata accepting pairs of words and we study some closure properties of this model. Our main result is that such alternating automata are not closed under complementation for non-unary alphabets. This improves a similar result of Kari and Moore for picture languages. We also show that these deterministic, non-deterministic and alternating automata are not closed under composition.

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Olivier Carton, Léo Exibard, Olivier Serre. 2017-09-30. Two-way Two-tape Automata. https://doi.org/10.1007/978-3-319-62809-7_10

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