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Ideal class groups and subgroups of real quadratic function fields

KunPeng Wang·Xianke Zhang
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Abstract

Here we study algebraic function fields K, give necessary and sufficient condition for the ideal class group $H(K)$ of any real quadratic function field $K$ to have a cyclic subgroup of order $n$, and obtain eight series of such fields $K$, with four of them NOT ERD-type or GERD-type.

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KunPeng Wang, Xianke Zhang. 2000-04-07. Ideal class groups and subgroups of real quadratic function fields. https://arxiv.org/abs/math/0004191

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