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arXiv · 2609.13793

Unrestricted 2DFA simulation of 1NFAs: A Quadratic Limitation to a New Lower Bound

Kehinde Adeogun·Christos A. Kapoutsis
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Abstract

A recent result by the present authors established a quadratic lower bound, in the worst case, for the increase in the number of states when a one-way nondeterministic finite automaton is converted to a two-way deterministic finite automaton. Although this simply matched a well-known pre-existing quadratic lower bound by Chrobak, it used a distinct proof method. We show that, much like Chrobak's, this new method is also unable to deliver any lower bound strictly greater than quadratic.

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Kehinde Adeogun, Christos A. Kapoutsis. 2026-09-15. Unrestricted 2DFA simulation of 1NFAs: A Quadratic Limitation to a New Lower Bound. https://arxiv.org/abs/2609.13793

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