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Transactions of the American Mathematical Society

ISSN 1088-6850(online) ISSN 0002-9947(print)



Linkage and sums of ideals

Author: Mark R. Johnson
Journal: Trans. Amer. Math. Soc. 350 (1998), 1913-1930
MSC (1991): Primary 13C40, 13C14
MathSciNet review: 1432202
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Abstract: It is shown (under mild conditions) that the sum of transversal ideals in a regular local ring cannot lie in the linkage class of a complete intersection. For a sum of geometrically linked Cohen-Macaulay ideals, we compute the depths of the conormal module and the first Koszul homology. As applications, we construct general examples of ideals which are strongly Cohen-Macaulay, strongly nonobstructed but not in the linkage class of a complete intersection, and Gorenstein ideals which are strongly nonobstructed but not syzygetic.

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Additional Information

Mark R. Johnson
Affiliation: Department of Mathematical Sciences, University of Arkansas, Fayetteville, Arkansas 72701

Received by editor(s): June 10, 1996
Article copyright: © Copyright 1998 American Mathematical Society

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