On 𝑛-widths in 𝐿^{∞}

Micchelli, Charles A.; Pinkus, Allan

doi:10.1090/S0002-9947-1977-0487187-1

On $n$-widths in $L^{\infty }$
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by Charles A. Micchelli and Allan Pinkus

Trans. Amer. Math. Soc. 234 (1977), 139-174

DOI: https://doi.org/10.1090/S0002-9947-1977-0487187-1

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Abstract:

The n-width in ${L^\infty }$ of certain sets determined by matrices and integral operators is determined. The notion of total positivity is essential in the analysis.

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