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arXiv · 1801.00517

Dedekind Sums with Even Denominators

Michael Kural
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Abstract

Let $S(a,b)$ denote the normalized Dedekind sum. We study the range of possible values for $S(a,b)=\frac{k}{q}$ with $\gcd(k,q)=1$. Girstmair proved local restrictions on $k$ depending on $q\pmod{12}$ and whether $q$ is a square and conjectured that these are the only restrictions possible. We verify the conjecture in the cases $q$ even, $q$ a square divisible by $3$ or $5$, and $2\le q\le 200$ (the latter by computer), and provide progress towards a general approach.

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Michael Kural. 2018-01-01. Dedekind Sums with Even Denominators. https://arxiv.org/abs/1801.00517

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