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arXiv · 1811.11407

The Heun-Askey-Wilson algebra and the Heun operator of Askey-Wilson type

Pascal Baseilhac·Satoshi Tsujimoto·Luc Vinet·Alexei Zhedanov
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Abstract

The Heun-Askey-Wilson algebra is introduced through generators $\{\boX,\boW\}$ and relations. These relations can be understood as an extension of the usual Askey-Wilson ones. A central element is given, and a canonical form of the Heun-Askey-Wilson algebra is presented. A homomorphism from the Heun-Askey-Wilson algebra to the Askey-Wilson one is identified. On the vector space of the polynomials in the variable $x=z+z^{-1}$, the Heun operator of Askey-Wilson type realizing $\boW$ can be characterized as the most general second order $q$-difference operator in the variable $z$ that maps polynomials of degree $n$ in $x=z+z^{-1}$ into polynomials of degree $n+1$.

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Pascal Baseilhac, Satoshi Tsujimoto, Luc Vinet, Alexei Zhedanov. 2018-11-28. The Heun-Askey-Wilson algebra and the Heun operator of Askey-Wilson type. https://doi.org/10.1007/s00023-019-00821-3

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