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On the Hartshorne--Speiser--Lyubeznik Theorem about Artinian modules with a Frobenius action

Rodney Y. Sharp
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Abstract

Let $R$ be a commutative Noetherian local ring of prime characteristic. The purpose of this paper is to provide a short proof of G. Lyubeznik's extension of a result of R. Hartshorne and R. Speiser about a module over the skew polynomial ring $R[x,f]$ (associated to $R$ and the Frobenius homomorphism $f$, in the indeterminate $x$) that is both $x$-torsion and Artinian over $R$.

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Rodney Y. Sharp. 2006-05-12. On the Hartshorne--Speiser--Lyubeznik Theorem about Artinian modules with a Frobenius action. https://arxiv.org/abs/math/0605330

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