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On the Continued Fraction Expansions of \(\sqrt{p}\) and \(\sqrt{2p}\) for Primes \(p\equiv 3\pmod 4\)

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Class Groups of Number Fields and Related Topics

Abstract

The oddness of the length of the period of the continued fraction expansion of the square root of an odd prime integer equal to 3 modulo 4 is well known. We determine its value modulo 4. We also give a similar result for the square root of twice an odd prime integer equal to 3 modulo 4.

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Acknowledgements

We thank Yasuhiro Kishi for pointing us Refs. [2, 7].

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Correspondence to Stéphane R. Louboutin .

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Louboutin, S.R. (2020). On the Continued Fraction Expansions of \(\sqrt{p}\) and \(\sqrt{2p}\) for Primes \(p\equiv 3\pmod 4\). In: Chakraborty, K., Hoque, A., Pandey, P. (eds) Class Groups of Number Fields and Related Topics. Springer, Singapore. https://doi.org/10.1007/978-981-15-1514-9_16

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