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Norm-one projections onto subspaces of finite codimension in ℓ1 andc 0

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Abstract

We study 1-complemented subspaces of the sequence spaces ℓ1 andc 0. In ℓ1, 1-complemented subspaces of codimensionn are those which can be obtained as intersection ofn 1-complemented hyperplanes. Inc 0, we prove a characterization of 1-complemented subspaces of finite codimension in terms of intersection of hyperplanes.

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Authors and Affiliations

  1. Dipartimento di Matematica, Via delle Brecce Bianche, 60100, ANCONA, ITALY

    M. Baronti

  2. Dipartimento di Matematica, Piazza Porta S. Donato 5, 40127, BOLOGNA, ITALY

    P. Papini

Authors
  1. M. Baronti
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  2. P. Papini
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Work prepared under the auspices of GNAFA-CNR (National Council of Research) and Minister of Public Instruction of Italy.

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Baronti, M., Papini, P. Norm-one projections onto subspaces of finite codimension in ℓ1 andc 0 . Period Math Hung 22, 161–174 (1991). https://doi.org/10.1007/BF01960506

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  • DOI: https://doi.org/10.1007/BF01960506

Mathematics subject classification numbers, 1980/85

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