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Heights on the finite projective line

Melvyn B. Nathanson
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Abstract

Define the height function h(a) = min{k+(ka\mod p): k=1,2,...,p-1} for a = 0,1,...,p-1. It is proved that the height has peaks at p, (p+1)/2, and (p+c)/3, that these peaks occur at a= [p/3], (p-3)/2, (p-1)/2, [2p/3], p-3,p-2, and p-1, and that h(a) \leq p/3 for all other values of a.

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Melvyn B. Nathanson. 2007-03-22. Heights on the finite projective line. https://arxiv.org/abs/math/0703646

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