English

The set of dimensions for which there are no linear perfect 2-error-correcting Lee codes has positive density

Information Theory 2018-04-26 v1 math.IT

Abstract

The Golomb-Welch conjecture states that there are no perfect ee-error-correcting Lee codes in Zn\mathbb{Z}^n (PL(n,e)PL(n,e)-codes) whenever n3n\geq 3 and e2e\geq 2. A special case of this conjecture is when e=2e=2. In a recent paper of A. Campello, S. Costa and the author of this paper, it is proved that the set N\mathcal{N} of dimensions n3n\geq 3 for which there are no linear PL(n,2)PL(n,2)-codes is infinite and #{nN:nx}x3ln(x)/2(1+o(1))\#\{n \in \mathcal{N}: n\leq x\} \geq \frac{x}{3\ln(x)/2} (1+o(1)). In this paper we present a simple and elementary argument which allows to improve the above result to #{nN:nx}4x25(1+o(1))\#\{n \in \mathcal{N}: n\leq x\} \geq \frac{4x}{25} (1+o(1)). In particular, this implies that the set N\mathcal{N} has positive (lower) density in Z+\mathbb{Z}^+.

Keywords

Cite

@article{arxiv.1804.09290,
  title  = {The set of dimensions for which there are no linear perfect 2-error-correcting Lee codes has positive density},
  author = {Claudio Qureshi},
  journal= {arXiv preprint arXiv:1804.09290},
  year   = {2018}
}