A note on best selection of quasi Descartes systems

Kazuaki Kitahara

doi:10.33993/jnaat382-910

Authors

Kazuaki Kitahara Kwansei Gakuin University, Japan

DOI:

https://doi.org/10.33993/jnaat382-910

Keywords:

Descartes Systems, best approximations

Abstract views: 218

Abstract

Let \(\{u_0, \dots, u_n\}\) be a quasi Descartes system of \(C[a, b]\) and \(p\) a positive number with \(1 < p < \infty\) or \(\infty\). In this note, we search for an \(m (\leqq n)\) dimensional subspace that possesses the least distance from \(u_n\) among all \(m (\leqq n)\) dimensional subspaces of \({\rm Span}\{ u_0, \ldots, u_{n-1}\}\).

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References

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