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Representing Primes as x^2 + 5y^2: An Inductive Proof that Euler Missed

Ying Zhang
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Abstract

We present an elementary inductive proof which Euler could have obtained, for the corresponding result as the title indicates, had he refined a bit his proof for Fermat's assertion on representing primes as two squares.

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Ying Zhang. 2007-02-11. Representing Primes as x^2 + 5y^2: An Inductive Proof that Euler Missed. https://arxiv.org/abs/math/0606547

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