Bourbaki

Exercise 10, § 3

Commutative Algebra, III, 247

Let A be a Zariski ring, m a defining ideal of the topology on A and E a finitely generated A-module. Show that, if E^\hat{E} is an A^\hat{A}-module admitting a system of generators with r elements, then the A-module E admits a system of generators with r elements (note that E/mEE/mE and E^/mE^\hat{E}/m\hat{E} are isomorphic and use Chapter 11, § 3, Corollary 2 to Proposition 4). Is the result valid if E is not assumed to be finitely generated (cf. Exercise 9)? Is it valid if we only assume that A is Noetherian (take A=ZA = \mathbf{Z})?

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Transcribed from the printed volume. Not translated.