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The essential ideal is a Cohen-Macaulay module

David J. Green
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Abstract

Let G be a finite p-group which does not contain a rank two elementary abelian p-group as a direct factor. Then the ideal of essential classes in the mod-p cohomology ring of G is a Cohen-Macaulay module whose Krull dimension is the p-rank of the centre of G. This basically answers in the affirmative a question posed by J. F. Carlson.

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David J. Green. 2004-02-26. The essential ideal is a Cohen-Macaulay module. https://doi.org/10.1090/s0002-9939-05-07887-1

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