English

On common index divisors and monogenity of certain number fields defined by $x^5+ax+b$

Number Theory 2023-06-21 v3

Abstract

The goal of this paper is to calculate explicitly the field index of any quintic number field KK generated by a complex root \al\al of a monic irreducible trinomial F(x)=x5+ax+bZ[x]F(x) = x^5+ax+b \in \Z[x]. In such a way we provide a complete answer to the Problem 22 of Narkiewicz \cite{WN}. Namely for every prime integer pp, we evaluate the highest power of pp dividing i(K)i(K). In particular, we give sufficient conditions on aa and bb, which guarantee the non monogenity of KK.

Keywords

Cite

@article{arxiv.2112.01133,
  title  = {On common index divisors and monogenity of certain number fields defined by $x^5+ax+b$},
  author = {Lhoussain El Fadil},
  journal= {arXiv preprint arXiv:2112.01133},
  year   = {2023}
}

Comments

Submitted. arXiv admin note: text overlap with arXiv:2111.05899, arXiv:2106.01252, arXiv:2109.08765