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Variations on Müntz's Theme

Published online by Cambridge University Press:  20 November 2018

Peter B. Borwein*
Affiliation:
Department of Mathematics, Dalhousie University, Halifax, Nova Scotia B3H 4H8
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Abstract

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We consider some variations of Muntz's classical theorem on when Span{xλi} is dense in C[0,1]. We prove, for example, that if then the collection of spaces is dense in C[0,1] if and only if lim sup(log n)/λn = ∞. Another variation concerns the denseness of the union of spaces of the form The derivations of these results require an examination of the location of the zeros of the associated Chebyshev polynomials.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1991

References

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