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, Volume 25, Issue 4, pp 377–386 | Cite as

Directly Indecomposables in Semidegenerate Varieties of Connected po-Groupoids

  • Pedro Sánchez Terraf
Article
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Abstract

We study varieties with a term-definable poset structure, po-groupoids. It is known that connected posets have the strict refinement property (SRP). In Sánchez Terraf and Vaggione (Trans Am Math Soc, in press) it is proved that semidegenerate varieties with the SRP have definable factor congruences and if the similarity type is finite, directly indecomposables are axiomatizable by a set of first-order sentences. We obtain such a set for semidegenerate varieties of connected po-groupoids and show its quantifier complexity is bounded in general.

Keywords

Connected poset Strict refinement property Semidegenerate variety Definable factor congruences 

Mathematics Subject Classifications (2000)

06A12 20M10 

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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.CIEM—Facultad de Matemática, Astronomía y Física (Fa.M.A.F.)Universidad Nacional de CórdobaCórdobaArgentina

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