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arXiv · 1503.07747

Confluent Chains of DBT: Enlarged Shape Invariance and New Orthogonal Polynomials

Yves Grandati·Christiane Quesne
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Abstract

We construct rational extensions of the Darboux-P\"oschl-Teller and isotonic potentials via two-step confluent Darboux transformations. The former are strictly isospectral to the initial potential, whereas the latter are only quasi-isospectral. Both are associated to new families of orthogonal polynomials, which, in the first case, depend on a continuous parameter. We also prove that these extended potentials possess an enlarged shape invariance property.

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Yves Grandati, Christiane Quesne. 2015-03-26. Confluent Chains of DBT: Enlarged Shape Invariance and New Orthogonal Polynomials. https://doi.org/10.3842/sigma.2015.061

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