Abstract
We provide a characterization of integers of the form described in the title in the context of class field theory. A more down-to-earth characterization is given when the extended class number is 1, 2, or 3. For completeness we present a formula for the extended class number. Some examples are also given.
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Communicated by J. Schoißengeier.
B. Cho was supported by the Dongguk University Research Fund of 2013.
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Cho, B. Integers of the form \(x^2 + ny^2\) . Monatsh Math 174, 195–204 (2014). https://doi.org/10.1007/s00605-013-0531-0
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DOI: https://doi.org/10.1007/s00605-013-0531-0