Skip to main content
2 of 6
cis -> \operatorname{cis}
LSpice
  • 12.9k
  • 4
  • 45
  • 69

Limit of $\sum cis(\pi\cdot \log \log n )$

Are there results, or can someone point me to reading, on computations of the following:

$\lim_n \sum_n \operatorname{cis}(\pi \cdot \log \log n)$

It would seem that there is reason to believe this should be something like $-\log(n)$. For example, see the graphic on this question which is the visual representation of $\sum_x (-1)^{\omega(x)}$ which for large $x$ is like $\sum_x (-1)^{\log \log (x)} = \sum_x \operatorname{cis}(\pi \cdot \log \log (x))$. On expectation, this looks something like $- \log n$.

I dont know where to start, sources would be nice, thank you!