arXiv math/02121662002-12-11math.FA

On a question of Haskell P. Rosenthal

Valentin Ferenczi, Anna Maria Pelczar, Christian Rosendal

备注：: 14 pages

英文摘要：

We consider a normalized basis in a Banach space with the following property: any normalized block sequence of the basis has a subsequence equivalent to the basis. We show that under uniformity or other natural assumptions, a basis with this property is equivalent to the unit vector basis of $c_0$ or $\ell_p$. We also address an analogous problem for spreading models.

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