Bulletin of the Korean Mathematical Society (대한수학회보)

Korean Mathematical Society (대한수학회)
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A NOTE ON CUBICALLY HYPONORMAL WEIGHTED SHIFTS

  • Li, Chunji (Institute of System Science Northeastern University) ;
  • Cho, Muneo (Department of Mathematics Faculty of Science Kanagawa University) ;
  • Lee, Mi Ryeong (Institute of Liberal Education Catholic University of Daegu)
  • Received : 2013.08.11
  • Published : 2014.07.31
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Abstract

In this paper, we show that any cubically hyponormal weighted shift with first two equal weights is flat. And we give an example of a weighted shift which is not cubically hyponormal but almost-cubically hyponormal.

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References

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Cited by

  1. Semi-cubic Hyponormality of Weighted Shifts with Stampfli Recursive Tail vol.88, pp.2, 2017, https://doi.org/10.1007/s00020-017-2373-y
  2. On Semi-cubically Hyponormal Weighted Shifts with First Two Equal Weights vol.56, pp.3, 2016, https://doi.org/10.5666/KMJ.2016.56.3.899
  3. On Positive Quadratic Hyponormality of a Unilateral Weighted Shift with Recursively Generated by Five Weights vol.7, pp.2, 2019, https://doi.org/10.3390/math7020212