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arXiv · 1812.11239

On the Radical of Multiperfect Numbers and Applications

Nithin Kavi·Xinyi Zhang·Viraj Jayam·Ajit Kadaveru
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Abstract

It is conjectured that for a perfect number $m,$ $\rm{rad}(m)\ll m^{\frac{1}{2}}.$ We prove bounds on the radical of multiperfect number $m$ depending on its abundancy index. Assuming the ABC conjecture, we apply this result to study gaps between multiperfect numbers, multiperfect numbers represented by polynomials. Finally, we prove that there are only finitely many multiperfect multirepdigit numbers in any base $g$ where the number of digits in the repdigit is a power of $2.$ This generalizes previous works of several authors including O. Klurman, F. Luca, P. Polack, C. Pomerance and others.

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Nithin Kavi, Xinyi Zhang, Viraj Jayam, Ajit Kadaveru. 2018-12-28. On the Radical of Multiperfect Numbers and Applications. https://arxiv.org/abs/1812.11239

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