English

Additive complements for two given asymptotic densities

Combinatorics 2022-07-05 v2 Number Theory

Abstract

Let 0αβ10\le \alpha \le \beta\le 1. For any finite set BNB\subset\mathbb{N}, we show that there exists a set ANA\subset\mathbb{N} such that d(A+B)=α\underline{d}(A+B) = \alpha and dˉ(A+B)=β\bar{d}(A+B) = \beta, where d(A+B)\underline{d}(A+ B) and dˉ(A+B)\bar{d}(A+B) are the lower and upper asymptotic densities of the set A+BA+B, respectively. This partially answers a question by Faisant et al. A theorem involving the so-called highly sparse sets was proved in the previous arXiv version of this note; however, as pointed out by Sai Teja Somu, the proof of the theorem was flawed. The theorem is now an open question.

Keywords

Cite

@article{arxiv.2106.07808,
  title  = {Additive complements for two given asymptotic densities},
  author = {Hung Viet Chu},
  journal= {arXiv preprint arXiv:2106.07808},
  year   = {2022}
}

Comments

4 pages. Remove Theorem 1.5 in the previous version

R2 v1 2026-06-24T03:12:05.940Z