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arXiv · 2603.25506

An integrality phenomenon

Florian Fürnsinn·Danylo Radchenko·Wadim Zudilin
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Abstract

We prove a general statement about the integrality of the sequences generated by a recursion of the following form: $nu_n$ equals a linear combination of $u_{n-1},u_{n-2},\dots,u_0$ with polynomial coefficients in $n$ of special form. This includes a conjectural integrality of the sequence related to the H\"ormander-Bernhardsson extremal function, for which we further give a direct proof as well.

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Florian Fürnsinn, Danylo Radchenko, Wadim Zudilin. 2026-03-26. An integrality phenomenon. https://arxiv.org/abs/2603.25506

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