English

Lebesgue-type estimates for greedy algorithms in quasi-Banach spaces

Functional Analysis 2025-08-28 v3

Abstract

We continue the study of Lebesgue-type parameters for various greedy algorithms in quasi-Banach spaces. First, we introduce a parameter that can be used with the quasi-greedy parameter to obtain the exact growth of the Lebesgue parameter for strong partially greedy bases. Second, we establish a new upper bound for the Lebesgue parameter for semi-greedy bases using the quasi-greedy and the squeeze symmetry parameters. Finally, we answer several open questions regarding the optimal power in various bounds proved in [F. Albiac, J. L. Ansorena, and P. M. Bern\'a, New parameters and Lebesgue-type estimates in greedy approximation, Forum Math. Sigma 10 (2022), 1-39].

Keywords

Cite

@article{arxiv.2508.16893,
  title  = {Lebesgue-type estimates for greedy algorithms in quasi-Banach spaces},
  author = {Miguel Berasategui and Pablo M. Berná and Hung Viet Chu and Andrea García},
  journal= {arXiv preprint arXiv:2508.16893},
  year   = {2025}
}