English

Partial sums of generalized Rabotnov function

Complex Variables 2023-09-06 v3

Abstract

Let (Rα,β,γ(z))m(z)=z+n=1mAnzn+1(\mathbb{R}_{\alpha ,\beta ,\gamma }(z))_{m}(z)=z+\sum_{n=1}^{m}A_{n}z^{n+1} be the sequence of partial sums of the normalized Rabotnov functions Rα,β,γ(z)=z+n=1Anzn+1\mathbb{R}_{\alpha ,\beta ,\gamma }(z)=z+\sum_{n=1}^{\infty }A_{n}z^{n+1} where An=βnΓ(γ+α)Γ((γ+α)(n+1)).A_{n}=\frac{\beta ^{n}\Gamma \left( \gamma +\alpha \right) }{\Gamma \left( \left( \gamma +\alpha \right) (n+1)\right) }. The purpose of the present paper is to determine lower bounds for \mathfrak{R}\left \{ \frac{\mathbb{R}_{\alpha ,\beta ,\gamma }(z)% }{(\mathbb{R}_{\alpha ,\beta ,\gamma })_{m}(z)}\right \} ,\mathfrak{R}% \left \{ \frac{(\mathbb{R}_{\alpha ,\beta ,\gamma })_{m}(z)}{\mathbb{R}% _{\alpha ,\beta ,\gamma }(z)}\right \} , \mathfrak{R}\left \{ \frac{\mathbb{R}_{\alpha ,\beta ,\gamma }(z)}{(\mathbb{% R}_{\alpha ,\beta ,\gamma })_{m}^{\prime }(z)}\right \} ,\mathfrak{R}% \left \{ \frac{(\mathbb{R}_{\alpha ,\beta ,\gamma })_{m}^{\prime }(z)}{% \mathbb{R}_{\alpha ,\beta ,\gamma }(z)}\right \} . Furthermore, we give lower bounds for \mathfrak{R}\left \{ \frac{\mathbb{I}\left[ \mathbb{R}% _{\alpha ,\beta ,\gamma }\right] (z)}{(\mathbb{I}\left[ \mathbb{R}_{\alpha ,\beta ,\gamma }\right] )_{m}(z)}\right \} and \mathfrak{R}\left \{ \frac{% (\mathbb{I}\left[ \mathbb{R}_{\alpha ,\beta ,\gamma }\right] )_{m}(z)}{% \mathbb{I}\left[ \mathbb{R}_{\alpha ,\beta ,\gamma }\right] (z)}\right \} where I[Rα,β,γ]\mathbb{I}\left[ \mathbb{R}_{\alpha ,\beta ,\gamma }\right] is the Alexander transform of Rα,β,γ\mathbb{R}_{\alpha ,\beta ,\gamma }. Several examples of the main results are also considered.

Keywords

Cite

@article{arxiv.2210.14294,
  title  = {Partial sums of generalized Rabotnov function},
  author = {Basem Aref Frasin},
  journal= {arXiv preprint arXiv:2210.14294},
  year   = {2023}
}
R2 v1 2026-06-28T04:30:11.934Z