Abstract We give necessary and sufficient conditions for the group of a rational maximal bifix code Z to be isomorphic with the F-group of Z ∩ F {Z\cap F} , when F is recurrent and Z ∩ F {Z\cap F} is rational. The case where F is uniformly recurrent, which is known to imply the finiteness of Z ∩ F {Z\cap F} , receives special attention. The proofs are done by exploring the connections with the structure of the free profinite monoid over the alphabet of F.

中文翻译：

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关于有理极大二分码群

摘要 我们给出了有理极大二分码 Z 的群与 Z ∩ F {Z\cap F} 的 F 群同构的充要条件，当 F 是循环且 Z ∩ F {Z\cap F}是理性的。F 是一致循环的情况，已知这意味着 Z ∩ F {Z\cap F} 的有限性，受到特别关注。证明是通过探索与 F 字母表上的自由超限幺半群结构的联系来完成的。