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arXiv · 2603.04268

Extreme and exposed points of shift-invariant spaces generated by Gaussian kernel and hyperbolic secant

Markus Valås Hagen·Alexander Ulanovskii·Denis Zelent·Ilya Zlotnikov
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Abstract

We characterize the extreme and exposed points of the unit ball (with respect to the $L^1$-norm) in the shift-invariant space generated by the Gaussian function, as well as in the quasi shift-invariant space generated by the hyperbolic secant.

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Markus Valås Hagen, Alexander Ulanovskii, Denis Zelent, Ilya Zlotnikov. 2026-03-04. Extreme and exposed points of shift-invariant spaces generated by Gaussian kernel and hyperbolic secant. https://arxiv.org/abs/2603.04268

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