Primes in arithmetic progressions to smooth moduli: A minorant version
Runbo Li
TL;DR
This paper addresses the distribution of primes in arithmetic progressions to smooth moduli by constructing a minorant $\rho(n)$ for the prime indicator $\mathbbm{1}_p(n)$. The author develops a sieve-based decomposition, rooted in Buchstab's identity, to control sums of $\rho(n)$ in residue classes modulo $q$ with $q \mid \prod_{p < x^{\delta}} p$, and proves a dispersion bound with distribution level $\frac{10}{19}$. The result improves on the prior bounds of Baker–Irving and Stadlmann by pushing the admissible modulus exponent to $\frac{10}{19}$ and provides a positive average lower bound for $\rho(n)$, though at the cost of a weaker pointwise lower bound compared to earlier work. The work clarifies the trade-offs between minorant strength and distribution level in the setting of primes in progressions to smooth moduli, with implications for bounded-gap questions under this framework.
Abstract
The author prove that there exists a function $ρ(n)$ which is a minorant for the prime indicator function $\mathbb{1}_{p}(n)$ and has distribution level $\frac{10}{19}$ in arithmetic progressions to smooth moduli. This refines the previous results of Baker--Irving and Stadlmann.
