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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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