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arXiv · 1310.6607

The 4-class group of real quadratic number fields

Franz Lemmermeyer
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Abstract

In this paper we give an elementary proof of results on the structure of 4-class groups of real quadratic number fields originally due to A. Scholz. In a second (and independent) section we strengthen C. Maire's result that the 2-class field tower of a real quadratic number field is infinite if its ideal class group has 4-rank at least $4$, using a technique due to F. Hajir.

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Franz Lemmermeyer. 2013-10-24. The 4-class group of real quadratic number fields. https://arxiv.org/abs/1310.6607

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