Existence of Smooth Numbers in Short Intervals;




Jain, Sarvagy

PublisherOxford University Press

2026

 Quarterly Journal of Mathematics

0033-5606

1464-3847

DOIhttps://doi.org/10.1093/qmath/haag010

https://doi.org/10.1093/qmath/haag010

https://research.utu.fi/converis/portal/detail/Publication/526510809



Let X ≥ y ≥ 2, and let u = log X/log y. We say a number is y-smooth if all of its prime factors are less than or equal to y. In this paper, we study the distribution of y-smooth numbers in short intervals. In particular, for y ≥ exp ((log X ) 2/3+ε), we show that the interval [x, x + h] contains a y-smooth number for almost all x ∈ [X, 2X ], provided h ≥ exp ((1 + ε ) ( 11/8 u log u + 4 log log X)), and X is sufficiently large depending ε. This result improves upon an earlier result by Matomäki. Additionally, we provide the corresponding ‘all intervals’ type result. Our approach relies on a strategically factorized Dirichlet polynomial, much like the earlier work of Matomäki. The improvement in our results stems from the integration of ideas introduced in the breakthrough work of Matomäki and Radziwiłł.


The author was supported by the Academy of Finland, Centre of Excellence (Grant No. 346307), and the University of Turku Graduate School Exactus fellowship while working on this project.


Last updated on 12/06/2026 12:18:12 PM