Journal of the Korean Mathematical Society (대한수학회지)

Korean Mathematical Society (대한수학회)
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ON A FAMILY OF COHOMOLOGICAL DEGREES

  • Cuong, Doan Trung (Institute of Mathematics and the Graduate University of Science and Technology Vietnam Academy of Science and Technology) ;
  • Nam, Pham Hong (College of Sciences Thai Nguyen University)
  • Received : 2019.04.28
  • Accepted : 2019.10.23
  • Published : 2020.05.01
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Abstract

Cohomological degrees (or extended degrees) were introduced by Doering, Gunston and Vasconcelos as measures for the complexity of structure of finitely generated modules over a Noetherian ring. Until now only very few examples of such functions have been known. Using a Cohen-Macaulay obstruction defined earlier, we construct an infinite family of cohomological degrees.

Keywords

Acknowledgement

Supported by : Vietnam National Foundation for Science and Technology Development (NAFOSTED)

The authors thank the anonymous referee for careful reading and many useful comments which help to improve the paper.

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