no. 6
On conjugacy of languages
RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 35 (2001) no. 6, pp. 535-550.

We say that two languages X and Y are conjugates if they satisfy the conjugacy equation XZ=ZY for some language Z. We study several problems associated with this equation. For example, we characterize all sets which are conjugated via a two-element biprefix set Z, as well as all two-element sets which are conjugates.

Classification : 68R15, 68Q70
Mots clés : conjugacy equation, languages, Conway's problem 
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     author = {Cassaigne, Julien and Karhum\"aki, Juhani and Ma\v{n}uch, J\'an},
     title = {On conjugacy of languages},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {535--550},
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     volume = {35},
     number = {6},
     year = {2001},
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Cassaigne, Julien; Karhumäki, Juhani; Maňuch, Ján. On conjugacy of languages. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 35 (2001) no. 6, pp. 535-550. http://archive.numdam.org/item/ITA_2001__35_6_535_0/

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