Endpoint weak boundedness of some polynomial expansions
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1
Universidad de Zaragoza
info
- 2 Departamento de Matemática Aplicada, Colegio Universitario de la Rioja, Logroño, Spain
ISSN: 0377-0427
Año de publicación: 1993
Volumen: 49
Número: 1
Páginas: 93-102
Tipo: Artículo
Otras publicaciones en: Journal of Computational and Applied Mathematics
Resumen
Let w(x) = (1 -x)α(1 + x)β on [- 1, 1], α,β≥ - 1 2, and for each function f let Snf be the nth expansion in the corresponding orthonormal polynomials. We show that the operators f → uSn(u-1f) are not of weak (p, p)-type, where u is another Jacobi weight and p is an endpoint of the interval of mean convergence. The same result is shown for expansions associated to measures of the form dv = w(x) dx + Σki=1Miδai. © 1993.