Gaps in Multiplicative Sidon Sets II

Abstract

With $ρ= \frac{13-\sqrt{69}}{10} \approx 0.47$, it was recently established that there exist multiplicative Sidon sets (sets without any non-trivial solutions to $ab = cd$) in $\{1, 2, \ldots, n\}$ with maximal gap size $\ll_{\varepsilon} n^{ρ+ \varepsilon}$. Here we improve upon this result and show that one can take $ρ= \frac{10}{33} \approx 0.303$ instead.