Moments of the shifted prime divisor function

Mikhail R. Gabdullin

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arXiv · 2505.24050

Moments of the shifted prime divisor function

Mikhail R. Gabdullin

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Abstract

Let $\omega^*(n) = \{d|n: d=p-1, \mbox{$p$ is a prime}\}$. We show that, for each integer $k\geq2$, $$ \sum_{n\leq x}\omega^*(n)^k \asymp x(\log x)^{2^k-k-1}, $$ where the implied constant may depend on $k$ only. This confirms a recent conjecture of Fan and Pomerance. Our proof uses a combinatorial identity for the least common multiple, viewed as a multiplicative analogue of the inclusion-exclusion principle, along with analytic tools from number theory.

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Mikhail R. Gabdullin. 2025-05-29. Moments of the shifted prime divisor function. https://arxiv.org/abs/2505.24050

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