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COMMUTING PROPERTIES OF EXT

Part of: Abelian groups

Published online by Cambridge University Press:  25 February 2013

PHILL SCHULTZ
PHILL SCHULTZ*
Affiliation:
School of Mathematics and Statistics, The University of Western Australia, Nedlands 6009, Australia email phill.schultz@uwa.edu.au
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Abstract

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We characterize the abelian groups $G$ for which the functors $\mathrm{Ext} (G, - )$ or $\mathrm{Ext} (- , G)$ commute with or invert certain direct sums or direct products.

Keywords

functors on abelian groupsextensionsself-sumsself-productstorsion-free abelian groupssplitterscotorsion groups

MSC classification

Secondary: 20K35: Extensions 20K40: Homological and categorical methods
Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 94 , Issue 2 , April 2013 , pp. 276 - 288
Copyright
Copyright ©2013 Australian Mathematical Publishing Association Inc. 

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