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Periodica Mathematica Hungarica

, Volume 22, Issue 3, pp 161–174 | Cite as

Norm-one projections onto subspaces of finite codimension in ℓ1 andc0

  • M. Baronti
  • P. Papini
Article

Abstract

We study 1-complemented subspaces of the sequence spaces ℓ1 andc0. In ℓ1, 1-complemented subspaces of codimensionn are those which can be obtained as intersection ofn 1-complemented hyperplanes. Inc0, we prove a characterization of 1-complemented subspaces of finite codimension in terms of intersection of hyperplanes.

Mathematics subject classification numbers, 1980/85

Primary 46B99 Secondary 41A65 

Key words and phrases

Sequence spaces projections 

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Copyright information

© Akadémiai Kiadó 1991

Authors and Affiliations

  • M. Baronti
    • 1
  • P. Papini
    • 2
  1. 1.Dipartimento di MatematicaANCONAITALY
  2. 2.Dipartimento di MatematicaBOLOGNAITALY

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