Publications Meetings The Profession Membership Programs Math Samplings Policy & Advocacy In the News About the AMS

Mobile Device Pairing
Green Open Access
Proceedings of the American Mathematical Society
Proceedings of the American Mathematical Society
ISSN 1088-6826(online) ISSN 0002-9939(print)


On openness of $ H\sb{n}$-locus and semicontinuity of $ n$th deviation

Author: Alfio Ragusa
Journal: Proc. Amer. Math. Soc. 80 (1980), 201-209
MSC: Primary 13D03; Secondary 13H10
MathSciNet review: 577744
Full-text PDF Free Access

Abstract | References | Similar Articles | Additional Information

Abstract: M. André has used the property $ {H_n}$, namely the vanishing of certain homology groups, and the deviation $ {\delta _n}$ to characterize some classes of rings. In the present paper the author establishes an inequality on the deviations and obtains a Nagata criterion for $ {H_n}$-locus and its openness for quotients of complete intersection rings and excellent rings. The upper-semicontinuity for $ {\delta _n}$ is also proved for the same classes of rings.

References [Enhancements On Off] (What's this?)

Similar Articles

Retrieve articles in Proceedings of the American Mathematical Society with MSC: 13D03, 13H10

Retrieve articles in all journals with MSC: 13D03, 13H10

Additional Information

PII: S 0002-9939(1980)0577744-1
Article copyright: © Copyright 1980 American Mathematical Society