English

On monogenity of certain pure number fields defined by $x^{2^u\cdot 3^v\cdot 5^t}-m$

Number Theory 2022-04-07 v1

Abstract

Let K=Q(α)K = \mathbb{Q} (\alpha) be a pure number field generated by a root α\alpha of a monic irreducible polynomial F(x)=x2u3v5tm F(x) = x^{2^u\cdot 3^v\cdot 5^t}-m, with m±1 m \neq \pm 1 a square free rational integer, uu, vv and tt three positive integers. In this paper, we study the monogenity of KK. We prove that if m≢1\md4m\not\equiv 1\md4, m≢±1\md9m\not\equiv \pm 1\md9, and m∉{±1,±7}\md25m\not\in\{\pm 1, \pm 7\}\md{25}, then KK is monogenic. But if {m1\md4m\equiv 1\md{4}} or m1\md9m\equiv 1\md9 or m1\md9m\equiv -1\md9 and u=2ku=2k for some odd integer kk or u2u\ge 2 and m1\md25m\equiv 1\md{25} or m1\md25m\equiv -1\md{25} and u=2ku=2k for some odd integer kk or u=v=1u=v=1 and m±82\md54m\equiv \pm 82\md{5^4}, then KK is not monogenic.

Keywords

Cite

@article{arxiv.2204.02436,
  title  = {On monogenity of certain pure number fields defined by $x^{2^u\cdot 3^v\cdot 5^t}-m$},
  author = {Lhoussain El Fadil},
  journal= {arXiv preprint arXiv:2204.02436},
  year   = {2022}
}

Comments

arXiv admin note: substantial text overlap with arXiv:2106.01252, arXiv:2112.01133, arXiv:2111.05899, arXiv:2106.00004; text overlap with arXiv:2203.13353