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DR-irreducibility of connected monounary algebras with a cycle. (English) Zbl 1079.08500
If $$K$$ is a class of monounary algebras then a monounary algebra $$A$$ is called retract irreducible in $$K$$ if, whenever $$A$$ is a retract of the product of some algebras in $$K$$, then $$A$$ is a retract of one of these algebras. The author studies the so-called DR-irreducibility of monounary algebras. An algebra $$A$$ is DR-irreducible if it is retract irreducible in the class of algebras isomorphic to retract of $$A$$. In the paper, all connected monounary algebras with a cycle which are DR-irreducible are described.

##### MSC:
 08A60 Unary algebras
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##### References:
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