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dd-sequences and partial Euler-Poincare' characteristics of Koszul complex

Nguyen Tu Cuong·Doan Trung Cuong
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Abstract

The aim of this paper is to introduce a new notion of sequences called dd-sequences and show that this notion may be convenient for studying the polynomial property of partial Euler-Poincare' characteristics of the Koszul complex with respect to the powers of a system of parameters. Some results about the dd-sequences, the partial Euler-Poincare' characteristics and the lengths of local cohomology modules are presented in the paper. There are also applications of dd-sequences on the structure of sequentially Cohen-Macaulay modules.

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Nguyen Tu Cuong, Doan Trung Cuong. 2005-07-11. dd-sequences and partial Euler-Poincare' characteristics of Koszul complex. https://arxiv.org/abs/math/0507200

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