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The Sidon constant of sets with three elements

Stefan Neuwirth
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Abstract

We solve an elementary extremal problem on trigonometric polynomials and obtain the exact value of the Sidon constant for sets with three elements {n0, n1, n2}: it is \sec(π/ 2n) for n = max(n1-n0, n2-n0, n2-n1) / gcd(n1-n0, n2-n0).

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Stefan Neuwirth. 2001-02-19. The Sidon constant of sets with three elements. https://arxiv.org/abs/math/0102145

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