Israel Journal of Mathematics

, Volume 107, Issue 1, pp 157–193 | Cite as

Convex unconditionality and summability of weakly null sequences

  • S. A. Argyros
  • S. Mercourakis
  • A. Tsarpalias


It is proved that every normalized weakly null sequence has a subsequence which is convexly unconditional. Further, a hierarchy of summability methods is introduced and with this we give a complete classification of the complexity of weakly null sequences.


Banach Space Finite Subset Inductive Assumption Spreading Model Summability Method 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© The Magnes Press 1998

Authors and Affiliations

  • S. A. Argyros
    • 1
  • S. Mercourakis
    • 1
  • A. Tsarpalias
    • 1
  1. 1.Department of MathematicsUniversity of AthensAthensGreece

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