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arXiv · 1903.01566

On Additive Divisor Sums and minorants of divisor functions

Kevin Smith·Julio Andrade
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Abstract

We establish asymptotic formulae for various correlations involving general divisor functions $d_k(n)$ and partial divisor functions $d_l(n,A)=\sum_{q|n:q\leq n^A}d_{l-1}(q)$, where $A\in[0,1]$ is a parameter and $k,l\in\mathbb{N}$ are fixed. Our results relate the parameter $A$ to the lengths of arithmetic progressions in which $d_k(n)$ is uniformly distributed. As applications to additive divisor sums, we establish new lower bounds and a new equivalent condition for the conjectured asymptotic. We also prove a Tauberian theorem for general additive divisor sums.

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Kevin Smith, Julio Andrade. 2019-03-04. On Additive Divisor Sums and minorants of divisor functions. https://arxiv.org/abs/1903.01566

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