{ "id": "2412.20443", "version": "v1", "published": "2024-12-29T11:54:55.000Z", "updated": "2024-12-29T11:54:55.000Z", "title": "Monogenic $S_3$-cubic polynomials and class numbers of associated quadratic fields", "authors": [ "Lenny Jones" ], "categories": [ "math.NT" ], "abstract": "We say that a monic polynomial $f(x)\\in {\\mathbb Z}[x]$ is monogenic if $f(x)$ is irreducible over ${\\mathbb Q}$ and $\\{1,\\theta,\\theta^2,\\ldots ,\\theta^{\\deg{f}-1}\\}$ is a basis for the ring of integers of ${\\mathbb Q}(\\theta)$, where $f(\\theta)=0$. In this article, we use a theorem due to Kishi and Miyake to give an explicit description of an infinite set ${\\mathcal F}$ of cubic polynomials $f(x)\\in {\\mathbb Z}[x]$, such that $f(x)$ satisfies the three conditions: ${\\rm Gal}_{{\\mathbb Q}}(f)\\simeq S_3$, the class number of the unique quadratic subfield of the splitting field of $f(x)$ is divisible by 3, and $f(x)$ is monogenic. Moreover, if $g(x)$ is any cubic polynomial satisfying these three conditions, then there exists a unique $f(x)\\in {\\mathcal F}$ such that $f(x)$ and $g(x)$ generate the same cubic extension over ${\\mathbb Q}$.", "revisions": [ { "version": "v1", "updated": "2024-12-29T11:54:55.000Z" } ], "analyses": { "keywords": [ "cubic polynomial", "associated quadratic fields", "class number", "unique quadratic subfield", "monic polynomial" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }