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Modules M such that \({\rm {\bf Ext}}_{{\bf \textit{R}}}^{\bf{1}}{({\bf \textit{M}},-)}\) Commutes with Direct Limits

Algebras and Representation Theory volume 16, pages 1799–1808 (2013)Cite this article

Abstract

We will use Watts’s theorem together with Lenzing’s characterization of finitely presented modules via commuting properties of the induced tensor functor in order to study commuting properties of covariant Ext-functors.

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Authors and Affiliations

  1. Faculty of Mathematics and Computer Science, Babeş-Bolyai University, Str. Mihail Kogălniceanu 1, 400084, Cluj-Napoca, Romania

    Simion Breaz

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  1. Simion Breaz
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Correspondence to Simion Breaz.

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Research supported by the CNCS-UEFISCDI grant PN-II-RU-TE-2011-3-0065.

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Breaz, S. Modules M such that \({\rm {\bf Ext}}_{{\bf \textit{R}}}^{\bf{1}}{({\bf \textit{M}},-)}\) Commutes with Direct Limits. Algebr Represent Theor 16, 1799–1808 (2013). https://doi.org/10.1007/s10468-012-9382-y

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  • DOI: https://doi.org/10.1007/s10468-012-9382-y

Keywords

  • Ext-functor
  • Direct limit
  • Hereditary ring

Mathematics Subject Classifications (2010)

  • 16E30
  • 16E60
  • 18G15