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arXiv · 2509.12270

A complete asymptotic expansion for the semi-exponential Post-Widder operators

Ulrich Abel·Octavian Agratini·Radu Paltanea
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Abstract

In the present paper, we study the asymptotic properties of the semi-exponential Post-Widder operator. It is connected with $p(x) = x^2$. The main result is a pointwise complete asymptotic expansion valid for locally smooth functions of exponential growth. All coefficients are derived and explicitly given. As a special case we recover the complete asymptotic expansion for the classical Post-Widder operator.

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Ulrich Abel, Octavian Agratini, Radu Paltanea. 2025-09-13. A complete asymptotic expansion for the semi-exponential Post-Widder operators. https://arxiv.org/abs/2509.12270

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