Korean Journal of Mathematics

The Kangwon-Kyungki Mathematical Society (강원경기수학회)
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WEAKLY SUBNORMAL WEIGHTED SHIFTS NEED NOT BE 2-HYPONORMAL

  • Lee, Jun Ik (Department of Mathematics Education Sangmyung University)
  • Received : 2014.02.09
  • Accepted : 2015.03.11
  • Published : 2015.03.30
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Abstract

In this paper we give an example which is a weakly subnormal weighted shift but not 2-hyponormal. Also, we show that every partially normal extension of an isometry T needs not be 2-hyponormal even though p.n.e.(T) is weakly subnormal.

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References

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