An improvement of the lower bound of the number of integers in Littlewood's conjecture

Abstract: In this paper, we improve the results in the author's previous paper \cite{Usu22}, which deals with the quantitative problem on Littlewood's conjecture. We show that, for any $0<\gamma<1$, any $(\alpha,\beta)\in\mathbb{R}^2$ except on a set with Hausdorff dimension about $\sqrt{\gamma}$, any small $0<\varepsilon<1$ and any large $N\in\mathbb{N}$, the number of integers $n\in[1,N]$ such that $n\langle n\alpha\rangle\langle n\beta\rangle<\varepsilon$ is greater than $\gamma(\log N)^2/(\log\log N)^2$ up to a universal constant.