Convergence of regularized greedy approximations
- Autores: Svetlov I.P.1
- 
							Afiliações: 
							- Lomonosov Moscow State University
 
- Edição: Volume 89, Nº 2 (2025)
- Páginas: 114-127
- Seção: Articles
- URL: https://journal-vniispk.ru/1607-0046/article/view/303949
- DOI: https://doi.org/10.4213/im9608
- ID: 303949
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Resumo
We consider a new version of a greedy algorithm in biorthogonal systems in separable Banach spaces.We consider approximations of an element $f$ via $m$-term greedy sum, which isconstructed from the expansion by choosing the first$m$ greatest in absolute value coefficients.It is known that the greedy algorithm does not always converge to the original element.We prove a theorem showing that the new version of a greedy algorithm(called the regularized greedy algorithm) always converges to the original element in Efimov–Stechkin spaces. We also construct examples that show the significance of the conditions of the main theorem.
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Sobre autores
Iurii Svetlov
Lomonosov Moscow State University
							Autor responsável pela correspondência
							Email: yuri.svetlov@math.msu.ru
				                					                																			                								without scientific degree, no status				                								 						
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