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The class of infinite dimensional neat reducts of quasi-polyadic algebras is not axiomatizable

✍ Scribed by Tarek Sayed Ahmed


Publisher
John Wiley and Sons
Year
2006
Tongue
English
Weight
135 KB
Volume
52
Category
Article
ISSN
0044-3050

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✦ Synopsis


SC, CA, QA and QEA denote the classes of Pinter's substitution algebras, Tarski's cylindric algebras, Halmos' quasi-polyadic algebras and quasi-polyadic equality algebras, respectively. Let ω ≤ α < β and let K ∈ {SC, CA, QA, QEA}. We show that the class of α-dimensional neat reducts of algebras in K β is not elementary. This solves a problem in [3]. Also our result generalizes results proved in [2] and [3].