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Smallest Graded Betti Numbers

✍ Scribed by Benjamin P Richert


Publisher
Elsevier Science
Year
2001
Tongue
English
Weight
153 KB
Volume
244
Category
Article
ISSN
0021-8693

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✦ Synopsis


It is known that given a Hilbert function H H, there need not exist a module which has uniquely the smallest graded Betti numbers among all modules attaining H H. In this paper we extend the previous example of this behavior to an infinite family and demonstrate with a second infinite family that even when the given Hilbert function is that of a complete intersection, a module with uniquely smallest graded Betti numbers need not exist. Finally we prove a conjecture of Geramita, Harima, and Shin concerning the non-existence of uniquely smallest graded Betti numbers among all Gorenstein rings attaining a given Hilbert function.


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