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arXiv · 2208.06704

On a conjecture of R. M. Murty and V. K. Murty

Yuchen Ding
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Abstract

Let $\omega^*(n)$ be the number of primes $p$ such that $p-1$ divides $n$. Recently, R. M. Murty and V. K. Murty proved that $$x(\log\log x)^3\ll\sum_{n\le x}\omega^*(n)^2\ll x\log x.$$ They further conjectured that there is some positive constant $C$ such that $$\sum_{n\le x}\omega^*(n)^2\sim Cx\log x$$ as $x\rightarrow \infty$. In this short note, we give the correct order of the sum by showing that $$\sum_{n\le x}\omega^*(n)^2\asymp x\log x.$$

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Yuchen Ding. 2022-08-13. On a conjecture of R. M. Murty and V. K. Murty. https://arxiv.org/abs/2208.06704

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