Fejér-Rogosinski theorem for the Neil algebra

Nilanjan Das; Jaydeb Sarkar

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arXiv · 2609.17114

Fejér-Rogosinski theorem for the Neil algebra

Nilanjan Das·Jaydeb Sarkar

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Abstract

Partial sums of the Taylor expansions of functions from the Neil algebra are uniformly bounded by their uniform norms on the ball of radius $r$ centered at the origin, where $r$ denotes the unique real root of \[ 4x^3 + x - 2 = 0. \] Moreover, this radius $r$ is optimal.

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Nilanjan Das, Jaydeb Sarkar. 2026-09-15. Fejér-Rogosinski theorem for the Neil algebra. https://arxiv.org/abs/2609.17114

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