一句话：构造确定性下推转换器，并证明它能压缩某个正规数字序列，从而正面回答一个开放问题。
本文研究下推自动机/转换器的压缩能力。此前 Becher、Heiber 与 Carton 留下问题：是否存在能被确定性下推转换器压缩的正规序列？作者通过构造一个确定性下推转换器，并给出一个由该转换器压缩的正规数字序列，对该问题给出肯定回答。结果表明，比有限状态转换器计算能力更强的下推机制能够压缩某些正规序列，从而深化了对正规性、压缩与自动机计算能力之间关系的理解。
In this paper, we give a deterministic pushdown transducer and a normal sequence of digits compressed by it. This solves positively a question left open in a previous paper by V. Becher, P. A. Heiber and the first author.
@article{paperbot2734,
title = {Deterministic pushdown automata can compress some normal sequences},
author = {Olivier Carton and Sylvain Perifel},
journal = {Logical Methods in Computer Science},
volume = {Volume 20, Issue 3},
year = {2024},
doi = {10.46298/lmcs-20(3:15)2024}
}