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On discrete orthogonal polynomials of several variables

Yuan Xu
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Abstract

Let $V$ be a set of isolated points in $\RR^d$. Define a linear functional $\CL$ on the space of real polynomials restricted on $V$, $\CL f = \sum_{x \in V} f(x)ρ(x)$, where $ρ$ is a nonzero function on $V$. Polynomial subspaces that contain discrete orthogonal polynomials with respect to the bilinear form $ = \CL(f g)$ are identified. One result shows that the discrete orthogonal polynomials still satisfy a three-term relation and Favard's theorem holds in this general setting.

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Yuan Xu. 2004-04-09. On discrete orthogonal polynomials of several variables. https://arxiv.org/abs/math/0401418

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