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arXiv · 1807.07605

Avoiding 3-Term Geometric Progressions in Hurwitz Quaternions

Megumi Asada·Bruce Fang·Eva Fourakis·Sarah Manski·Nathan McNew·Steven J. Miller·Gwyneth Moreland·Ajmain Yamin·Sindy Xin Zhang
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Abstract

Several recent papers have considered the problem of how large a subset of integers can be without containing any 3-term geometric progressions. This problem has also recently been generalized to rings of integers in quadratic number fields and polynomial rings over finite fields. We study the analogous problem in the Hurwitz quaternion order to see how non-commutativity affects the problem. We compute an exact formula for the density of a 3-term geometric-progression-free set of Hurwitz quaternions arising from a greedy algorithm and derive upper and lower bounds for the supremum of upper densities of 3-term geometric-progression-free sets of Hurwitz quaternions.

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Megumi Asada, Bruce Fang, Eva Fourakis, Sarah Manski, Nathan McNew, Steven J. Miller, Gwyneth Moreland, Ajmain Yamin, Sindy Xin Zhang. 2018-07-19. Avoiding 3-Term Geometric Progressions in Hurwitz Quaternions. https://arxiv.org/abs/1807.07605

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