Deformed Homogeneous Polynomials and the Generalized $q$-Exponential Operator
Ronald Orozco López
TL;DR
The paper develops a unified framework of deformed polynomials and hypergeometric series built around a deformed $q$-exponential, centering on the two-parameter family $R_n(x,y;u|q)$ and its specializations to Rogers–Szegö, Stieltjes–Wigert, and Exton polynomials. It introduces the $u$-deformed $q$-exponential operator $\mathop{\hbox{E}}(yD_q|u)$, which directly generates $R_n$ and yields a suite of operator identities linking these polynomials to various deformed hypergeometric objects. The work then develops a comprehensive set of generating functions, transformation formulas, Mehler-type and Rogers-type formulas, and generalized ${}_{r}\Phi_{s}$ series, providing generalized $q$-binomial theorems and Heine transformations with deformations controlled by $u$ (and related parameters). By deriving $q$-difference equations and hypergeometric representations, the paper unifies and extends classical results for Rogers–Szegö, Saad’s generalizations, Srivastava–Agarwal-type formulas, and Rogers–Ramanujan constructions, with potential applications to related orthogonal polynomials and $q$-series identities.
Abstract
This paper introduces the deformed homogeneous polynomials $\mathrm{R}_{n}(x,y;u|q)$. These polynomials generalize some classical polynomials: the Rogers-Szegö polynomials $\mathrm{h}_{n}(x|q)$, the generalized Rogers-Szegö polynomials $\mathrm{r}_{n}(x,y)$, the Stieljes-Wigert polynomials $\mathrm{S}_{n}(x;q)$, among others. Basic properties of the polynomial $\mathrm{R}_{n}$ are given, along with recurrence relations, its $q$-difference equation, and representations. Generating functions for the polynomials $\mathrm{R}_{n}(x,y;u|q)$ are given. These functions include generalizations of the Mehler and Rogers formulas. In addition, generalizations of the $q$-binomial formula and the Heine transformation formula are obtained. These results are obtained via the $u$-deformed $q$-exponential operator $\mathrm{E}(yD_{q}|u)$, defined here. From this operator, we obtain for free the operators T$(yD_{q})$ the Chen, $\mathrm{R}(yD_{q})$ of Saad, $\mathcal{E}(yD_{q})$ of Exton, and $\mathcal{R}(yD_{q})$ of Rogers-Ramanujan when $u=1,q,\sqrt{q},q^2$, respectively. We introduce the deformed basic hypergeometric series ${}_{r}Φ_{s}$, a generalization of the classical basic hypergeometric series. New transformation formulas for basic hypergeometric series are obtained.
