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arXiv · 1801.08740

The Toda and Painlev\'e Systems Associated with Semiclassical Matrix-Valued Orthogonal Polynomials of Laguerre Type

Mattia Cafasso·Manuel D. de la Iglesia
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Abstract

Consider the Laguerre polynomials and deform them by the introduction in the measure of an exponential singularity at zero. In [Chen Y., Its A., J. Approx. Theory 162 (2010), 270-297, arXiv:0808.3590] the authors proved that this deformation can be described by systems of differential/difference equations for the corresponding recursion coefficients and that these equations, ultimately, are equivalent to the Painlev\'e III equation and its B\"acklund/Schlesinger transformations. Here we prove that an analogue result holds for some kind of semiclassical matrix-valued orthogonal polynomials of Laguerre type.

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Mattia Cafasso, Manuel D. de la Iglesia. 2018-01-26. The Toda and Painlev\'e Systems Associated with Semiclassical Matrix-Valued Orthogonal Polynomials of Laguerre Type. https://doi.org/10.3842/sigma.2018.076

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