Mono-unary condition for algebras with easy direct limits
DOI:
https://doi.org/10.64700/altay.5Keywords:
Algebra, direct limit, retract, operation, endomorphismAbstract
Let \(\mathcal{A}\) be an algebra such that exactly algebras isomorphic to a retract of \(\mathcal{A}\) can be constructed from \(\mathcal{A}\) by direct limits. One condition which is satisfied for \(\mathcal{A}\) in the case that \(\mathcal{A}\) has a unary term operation which is an endomorphism of \(\mathcal{A}\) at the same time is presented. A bijective mapping occurs in this condition and mono-unary algebras are used substantially.
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