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Skipped Blocking and other Decompositions in Banach spaces

Steven F. Bellenot
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Abstract

Necessary and sufficient conditions are given for when a sequence of finite dimensional subspaces (X_n) can be blocked to be a skipped blocking decompositon (SBD). These are very similar to known results about blocking of biorthogonal sequences. A separable space $X$ has PCP, if and only if, every norming decomposition (X_n) can be blocked to be a boundedly complete SBD. Every boundedly complete SBD is a JT-decomposition.

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Steven F. Bellenot. 2005-02-22. Skipped Blocking and other Decompositions in Banach spaces. https://arxiv.org/abs/math/0408004

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