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arXiv · 2606.00663

Bandwidth of Nondeterministic Finite Automata

Da-Jung Cho·Szilárd Zsolt Fazekas·Daihei Ise·Shinnosuke Seki·Wataru Tamehira·Max Wiedenhöft
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Abstract

Co-transcriptional splicing generates RNA sequences from a DNA template by deleting subsequences nondeterministically. Recent work showed how to encode an NFA into such a template, but the construction requires deleting subsequences whose length grows with the distance between states, which makes such deletions unlikely under the local nature of co-transcriptional splicing. We introduce $k$-bandwidth NFAs, in which transitions span at most $k$ states. These automata form a strict hierarchy of language classes. For finite languages, bandwidth $2$ suffices, and bandwidth $1$ can be decided in polynomial-time when the language is presented as a list of words. Minimizing the bandwidth is NP-hard even for fixed $k \geq 2$.

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Da-Jung Cho, Szilárd Zsolt Fazekas, Daihei Ise, Shinnosuke Seki, Wataru Tamehira, Max Wiedenhöft. 2026-05-30. Bandwidth of Nondeterministic Finite Automata. https://arxiv.org/abs/2606.00663

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