On Quadratic Gauss Sums and Variations Thereof
  A number of new terminating series involving $\sin(n^2/k)$ and $\cos(n^2/k)$ are presented and connected to Gauss quadratic sums. Several new closed forms of generic Gauss quadratic sums are obtained and previously known results are generalized. 
Michael S. Milgram and Larry Glasser
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