A note on the coefficients of Hilbert polynomial (Q757500)

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scientific article; zbMATH DE number 4191845
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A note on the coefficients of Hilbert polynomial
scientific article; zbMATH DE number 4191845

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    A note on the coefficients of Hilbert polynomial (English)
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    1990
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    Let (Q,m) be a local ring and q an m-primary ideal. Then \(\ell (Q/m^{n+1})= e_ 0 \begin{pmatrix} n+d\\ d \end{pmatrix}- e_ 1\begin{pmatrix} n+d- 1\\ d-1 \end{pmatrix}+... +(-1)^ de_ d\). Of course \(e_ 0\) is positive and it has been shown that also \(e_ 1\) (by \textit{Northcott}) and \(e_ 2\) (by \textit{Narita}) are positive. Narita also gave an example of a Cohen-Macaulay ring with an m-primary ideal, such that \(e_ 3\) is negative. In this note it is shown that for each \(d>2\) there is a Cohen-Macaulay ring with an m-primary ideal, such that \(e_ d>0\).
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    Hilbert polynomial
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    Hilbert coefficients
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    Cohen-Macaulay ring
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