Random Deterministic Automata With One Added Transition
<|reference_start|>Random Deterministic Automata With One Added Transition: Every language recognized by a non-deterministic finite automaton can be recognized by a deterministic automaton, at the cost of a potential increase of the number of states, which in the worst case can go from $n$ states to $2^n$ states. In this article, we investigate this classical result in a probabilistic setting where we take a deterministic automaton with $n$ states uniformly at random and add just one random transition. These automata are almost deterministic in the sense that only one state has a non-deterministic choice when reading an input letter. In our model, each state has a fixed probability to be final. We prove that for any $d\geq 1$, with non-negligible probability the minimal (deterministic) automaton of the language recognized by such an automaton has more than $n^d$ states; as a byproduct, the expected size of its minimal automaton grows faster than any polynomial. Our result also holds when each state is final with some probability that depends on $n$, as long as it is not too close to $0$ and $1$, at distance at least $\Omega(\frac1{\sqrt{n}})$ to be precise, therefore allowing models with a sublinear number of final states in expectation.<|reference_end|>
@article{carayol2024random,
    title={Random Deterministic Automata With One Added Transition},
    author={Arnaud Carayol, Philippe Duchon, Florent Koechlin, Cyril Nicaud},
    journal={arXiv preprint arXiv:2402.06591},
    year={2024},
    archivePrefix={arXiv},
    eprint={2402.06591},
    primaryClass={cs.FL cs.LO}
}