{ "id": "1003.2221", "version": "v2", "published": "2010-03-10T22:35:57.000Z", "updated": "2010-03-13T07:27:07.000Z", "title": "Transcendence of generating functions whose coefficients are multiplicative", "authors": [ "Jason P. Bell", "Nils Bruin", "Michael Coons" ], "comment": "25 pages", "categories": [ "math.NT" ], "abstract": "In this paper, we give a new proof and an extension of the following result of B\\'ezivin. Let $f:\\B{N}\\to K$ be a multiplicative function taking values in a field $K$ of characteristic 0 and write $F(z)=\\sum_{n\\geq 1} f(n)z^n\\in K[[z]]$ for its generating series. Suppose that $F(z)$ is algebraic over $K(z)$. Then either there is a natural number $k$ and a periodic multiplicative function $\\chi(n)$ such that $f(n)=n^k \\chi(n)$ for all $n$, or $f(n)$ is eventually zero. In particular, $F(z)$ is either transcendental or rational. For $K=\\B{C}$, we also prove that if $F(z)$ is a $D$-finite generating series of a multiplicative function, then $F(z)$ is either transcendental or rational.", "revisions": [ { "version": "v2", "updated": "2010-03-13T07:27:07.000Z" } ], "analyses": { "keywords": [ "generating functions", "transcendence", "coefficients", "natural number", "finite generating series" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1003.2221B" } } }