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arXiv · 2103.08303

Weighted $L^2$-Norms of Gegenbauer polynomials

Johann S. Brauchart·Peter J. Grabner
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Abstract

We study integrals of the form \begin{equation*} \int_{-1}^1(C_n^{(\lambda)}(x))^2(1-x)^\alpha (1+x)^\beta\, dx, \end{equation*} where $C_n^{(\lambda)}$ denotes the Gegenbauer-polynomial of index $\lambda>0$ and $\alpha,\beta>-1$. We give exact formulas for the integrals and their generating functions, and obtain asymptotic formulas as $n\to\infty$.

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Johann S. Brauchart, Peter J. Grabner. 2021-03-15. Weighted $L^2$-Norms of Gegenbauer polynomials. https://arxiv.org/abs/2103.08303

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