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arXiv · 1910.11556

Discriminants of number fields and surjectivty of trace homomorphism on rings of integers

Francesco Battistoni
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Abstract

In this note we give a brief survey of the most elementary criteria used to determine the surjectivity of the trace operator on the ring of integers of a number field $K$. Furthermore, we introduce an easy to state yet unknown surjectivity criterion depending only on the prime factorization of the degree $n$ of $K$ and on the squarefree part of the discriminant $d_K$.

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Francesco Battistoni. 2019-10-25. Discriminants of number fields and surjectivty of trace homomorphism on rings of integers. https://arxiv.org/abs/1910.11556

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