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A morphic representation of EOL languages and other ETOL languages. (English) Zbl 0579.68046
Summary: The following morphic characterization of EOL languages is established. The family of EOL languages equals the family of all languages of the form h(L$$\cap R)$$ where h is a morphism, R is a regular language and L is the maximal solution of an equation $$f(X)=g(X)$$, where f is a morphism, g is a coding and X is a language variable. It is shown that if g is allowed to be a weak coding, then a larger family of languages is obtained, which however is strictly contained in the family of ETOL languages.

##### MSC:
 68Q45 Formal languages and automata
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##### References:
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