On the two differences l(I^*/R)-l(R/I) and rl(R/I)-l(I^*/R)

Anna Oneto; Elsa Zatini

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arXiv · math/0603244

On the two differences l(I^/R)-l(R/I) and rl(R/I)-l(I^/R)

Anna Oneto·Elsa Zatini

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Abstract

Let R be a one-dimensional local Noetherian domain, which is supposed analytically irreducible and residually rational, and let I be a proper ideal of R. Our purpose is to study the two numbers l(I^*/R)-l(R/I) and rl(R/I)-l(I^*/R) (l denotes the length, r the Cohen-Macaulay type) already considered in the literature under various points of view. The basic idea is the expression of these invariants in terms of the type sequence.

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Anna Oneto, Elsa Zatini. 2006-03-10. On the two differences l(I^*/R)-l(R/I) and rl(R/I)-l(I^*/R). https://arxiv.org/abs/math/0603244

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