Abstract
It is proved that if Σ ∞ i=1 X i is a non-convergent series in a Banach spaceX such that Σ ∞ i=1 |f(X i )|<∞ for all extreme pointsf of the unit ball ofX*, thenX contains a subspace isomorphic toc 0, improving a result of Bessaga and Pelczynski. The proof uses Fonf’s result that Lindenstrauss-Phelps spaces contain isomorphs ofc 0.
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Supported in part by NSF-MCS-8002393.
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Elton, J. Extremely weakly unconditionally convergent series. Israel J. Math. 40, 255–258 (1981). https://doi.org/10.1007/BF02761366
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DOI: https://doi.org/10.1007/BF02761366