Approximation of holomorphic functions in Banach spaces admitting a Schauder decomposition
Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 5, Volume 5 (2006) no. 1, p. 13-19

Let $X$ be a complex Banach space. Recall that $X$ admits a finite-dimensional Schauder decomposition if there exists a sequence ${\left\{{X}_{n}\right\}}_{n=1}^{\infty }$ of finite-dimensional subspaces of $X,$ such that every $x\in X$ has a unique representation of the form $x={\sum }_{n=1}^{\infty }{x}_{n},$ with ${x}_{n}\in {X}_{n}$ for every $n.$ The finite-dimensional Schauder decomposition is said to be unconditional if, for every $x\in X,$ the series $x={\sum }_{n=1}^{\infty }{x}_{n},$ which represents $x,$ converges unconditionally, that is, ${\sum }_{n=1}^{\infty }{x}_{\pi \left(n\right)}$ converges for every permutation $\pi$ of the integers. For short, we say that $X$ admits an unconditional F.D.D.We show that if X admits an unconditional F.D.D. then the following Runge approximation property holds:

Classification:  32H02
@article{ASNSP_2006_5_5_1_13_0,
author = {Meylan, Francine},
title = {Approximation of holomorphic functions in Banach spaces admitting a Schauder decomposition},
journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
publisher = {Scuola Normale Superiore, Pisa},
volume = {Ser. 5, 5},
number = {1},
year = {2006},
pages = {13-19},
zbl = {1150.46017},
mrnumber = {2240163},
language = {en},
url = {http://www.numdam.org/item/ASNSP_2006_5_5_1_13_0}
}

Meylan, Francine. Approximation of holomorphic functions in Banach spaces admitting a Schauder decomposition. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Serie 5, Volume 5 (2006) no. 1, pp. 13-19. http://www.numdam.org/item/ASNSP_2006_5_5_1_13_0/

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