On the special harmonic numbers $H_{\lfloor p/9 \rfloor}$ and $H_{\lfloor p/18 \rfloor}$ modulo $p$

John Blythe Dobson

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arXiv · 2302.02027

On the special harmonic numbers $H_{\lfloor p/9 \rfloor}$ and $H_{\lfloor p/18 \rfloor}$ modulo $p$

John Blythe Dobson

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Abstract

Building on work of Zhi-Hong Sun, we establish congruences for the special harmonic numbers $H_\lfloor p/9 \rfloor$ and $H_{\lfloor p/18 \rfloor}$ modulo $p$, which contain respectively three and four distinct arithmetic components. We also obtain a complete determination modulo $p$ of the corresponding families of sums of reciprocals of the type studied by Dilcher and Skula. Applications to the first case of Fermat's Last Theorem are considered.

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John Blythe Dobson. 2023-02-03. On the special harmonic numbers $H_{\lfloor p/9 \rfloor}$ and $H_{\lfloor p/18 \rfloor}$ modulo $p$. https://arxiv.org/abs/2302.02027

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