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On the complemented subspaces of X_p

Dale E. Alspach
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Abstract

In this paper we prove some results related to the problem of isomorphically classifying the complemented subspaces of $X_{p}$. We characterize the complemented subspaces of $X_{p}$ which are isomorphic to $X_{p}$ by showing that such a space must contain a canonical complemented subspace isomorphic to $X_{p}.$ We also give some characterizations of complemented subspaces of $X_{p}$ isomorphic to $\ell_{p}\oplus \ell_{2}.$

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Dale E. Alspach. 1990-07-20. On the complemented subspaces of X_p. https://arxiv.org/abs/math/9201214

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