https://en.wikipedia.org/wiki/Modular_arithmetic
Modular arithmetic - Wikipedia
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https://www.nybooks.com/articles/1985/02/28/the-twins-and-modular-arithmetic/
The Twins and Modular Arithmetic | Oliver Sacks | The New York Review of Books
Sep 15, 2020 - When he was shown the manuscript of this paper, Israel Rosenfield pointed out that there are other arithmetics, higher and simpler than the
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