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Small gaps between almost-twin primes

Number Theory 2025-07-17 v2

Abstract

Let mNm \in \mathbb{N} be large. We show that there exist infinitely many primes q1<<qm+1q_{1}< \cdot\cdot\cdot < q_{m+1} such that qm+1q1=O(e7.63m) q_{m+1}-q_{1}=O(e^{7.63m}) and qj+2q_{j}+2 has at most 7.36mlog2+4logmlog2+21 \frac{7.36m}{\log 2} + \frac{4\log m}{\log 2} + 21 prime factors for each 1jm+11 \leq j \leq m+1. This improves the previous result of Li and Pan, replacing m4e8mm^{4}e^{8m} by e7.63me^{7.63m} and 16mlog2+5logmlog2+37\frac{16m}{\log 2} + \frac{5\log m}{\log 2} + 37 by 7.36mlog2+4logmlog2+21\frac{7.36m}{\log 2} + \frac{4\log m}{\log 2} + 21. The main inputs are the Maynard-Tao sieve, a minorant for the indicator function of the primes constructed by Baker and Irving, for which a stronger equidistribution theorem in arithmetic progressions to smooth moduli is applicable, and Tao's approach previously used to estimate xn<2x1P(n)1P(n+12)ωn\sum_{x \leq n < 2x} \mathbf{1}_{\mathbb{P}}(n)\mathbf{1}_{\mathbb{P}}(n+12)\omega_{n}, where 1P\mathbf{1}_{\mathbb{P}} stands for the characteristic function of the primes and ωn\omega_{n} are multidimensional sieve weights.

Keywords

Cite

@article{arxiv.2402.00748,
  title  = {Small gaps between almost-twin primes},
  author = {Bin Chen},
  journal= {arXiv preprint arXiv:2402.00748},
  year   = {2025}
}

Comments

21 pages. Revised version, accepted for publication in Forum Mathematicum

R2 v1 2026-06-28T14:34:46.754Z