Large sets avoiding infinite arithmetic / geometric progressions
Abstract
We study some variants of the Erd\H{o}s similarity problem. We pose the question if every measurable subset of the real line with positive measure contains a similar copy of an infinite geometric progression. We construct a compact subset of the real line such that is a Lebesgue density point of , but does not contain any (non-constant) infinite geometric progression. We give a sufficient density type condition that guarantees that a set contains an infinite geometric progression. By slightly improving a recent result of Bradford, Kohut and Mooroogen arXiv:2205.04786, we construct a closed set such that the measure of tends to at infinity but does not contain any infinite arithmetic progression. We also slightly improve a more general recent result by Kolountzakis and Papageorgiou arXiv:2208.02637 for more general sequences. We give a sufficient condition that guarantees that a given Cantor type set contains at least one infinite geometric progression with any quotient between and . This can be applied to most symmetric Cantor sets of positive measure.
Cite
@article{arxiv.2210.09284,
title = {Large sets avoiding infinite arithmetic / geometric progressions},
author = {Alex Burgin and Samuel Goldberg and Tamás Keleti and Connor MacMahon and Xianzhi Wang},
journal= {arXiv preprint arXiv:2210.09284},
year = {2023}
}