arXiv · 2101.04519
We give a transcription of a letter from Eisenstein's parents to Gauss, and an unpublished proof of the quadratic reciprocity law by Eisenstein using the tangent function.
Franz Lemmermeyer. 2021-01-10. Ein Brief von Eisensteins Eltern an Gauss. https://arxiv.org/abs/2101.04519
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