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ON THE ASSOCIATED PRIMES OF LOCAL COHOMOLOGY

Published online by Cambridge University Press:  05 February 2018

HAILONG DAO
Affiliation:
Department of Mathematics, University of Kansas, Lawrence, KS 66045-7523, USA email [email protected]
PHAM HUNG QUY
Affiliation:
Department of Mathematics, FPT University Ha Noi, and Thang Long Institute of Mathematics and Applied Sciences, Thang Long University Ha Noi, Vietnam email [email protected]

Abstract

Let $R$ be a commutative Noetherian ring of prime characteristic $p$. In this paper, we give a short proof using filter regular sequences that the set of associated prime ideals of $H_{I}^{t}(R)$ is finite for any ideal $I$ and for any $t\geqslant 0$ when $R$ has finite $F$-representation type or finite singular locus. This extends a previous result by Takagi–Takahashi and gives affirmative answers for a problem of Huneke in many new classes of rings in positive characteristic. We also give a criterion about the singularities of $R$ (in any characteristic) to guarantee that the set $\operatorname{Ass}H_{I}^{2}(R)$ is always finite.

Type
Article
Copyright
© 2018 Foundation Nagoya Mathematical Journal  

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Footnotes

This paper was done while the second author was visiting Vietnam Institute for Advanced Study in Mathematics.

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