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An elementary proof of Gorny's inequality

Published online by Cambridge University Press:  14 November 2011

C. Fabry
Affiliation:
Institut Mathematique, Université Catholique de Louvain, chemin du Cyclotron 2, B-1348 Louvain-la-Neuve, Belgium

Synopsis

Gorny's inequality provides upper bounds for the sup-norms ∥f(k) of a function f over an interval [a, b] for k = 1, …, n − 1, assuming the sup-norms of f and f(n) to be given. We present a simple proof of that inequality and obtain sharper estimates of the constants contained in that inequality, compared with the original verison of Gorny.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1987

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