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arXiv · 1307.2508

Basic sequences and spaceability in $\ell_p$ spaces

Daniel Cariello·Juan B. Seoane-Sepúlveda
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Abstract

Let $X$ be a sequence space and denote by $Z(X)$ the subset of $X$ formed by sequences having only a finite number of zero coordinates. We study algebraic properties of $Z(X)$ and show (among other results) that (for $p \in [1,\infty]$) $Z(\ell_p)$ does not contain infinite dimensional closed subspaces. This solves an open question originally posed by R. M. Aron and V. I. Gurariy in 2003 on the linear structure of $Z(\ell_\infty)$. In addition to this, we also give a thorough analysis of the existing algebraic structures within the set $X \setminus Z(X)$ and its algebraic genericity.

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Daniel Cariello, Juan B. Seoane-Sepúlveda. 2013-07-09. Basic sequences and spaceability in $\ell_p$ spaces. https://arxiv.org/abs/1307.2508

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