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arXiv · 2606.31677

Conjectures of Bernstein and Erd\H os for weighted Lagrange interpolation on the halfline with exponential weights

Abstract

Let I=[a,b] and consider the degree n Lagrange interpolation at the nodes x, where x\in S:={x=(x_0,x_1,...,x_n):a=x_0 m_j(x). The conjectures were proved by Kilgore and de Boor--Pinkus in 1978. Since then, analogous results were obtained only for a few cases when interpolation is made to certain very special spaces of polynomials, or when we apply weighted interpolation with rather special weights. Worse than that, it turned out that published proofs of results on infinite intervals and weighted interpolation were seriously flawed. Here we prove the Bernstein and Erd\H os Conjectures for the case of exponentially weighted polynomials on the halfline. This is the first proof of these conjectures in a situation where, contrary to all existing successful proofs, we encounter singularity of certain derivative matrices.

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BibTeXRIS

Szilárd Gy. Révész, Patricia Szokol. 2026-06-30. Conjectures of Bernstein and Erd\H os for weighted Lagrange interpolation on the halfline with exponential weights. https://arxiv.org/abs/2606.31677

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