{ "id": "1202.1335", "version": "v3", "published": "2012-02-07T02:36:32.000Z", "updated": "2012-04-04T03:35:16.000Z", "title": "Representations of analytic functions as infinite products and their application to numerical computations", "authors": [ "Marcin Mazur", "Bogdan V. Petrenko" ], "comment": "Several editorial changes have been made", "categories": [ "math.NT" ], "abstract": "Let $D$ be an open disk of radius $\\le 1$ in $\\mathbb C$, and let $(\\epsilon_n)$ be a sequence of $\\pm 1$. We prove that for every analytic function $f: D \\to \\mathbb C$ without zeros in $D$, there exists a unique sequence $(\\alpha_n)$ of complex numbers such that $f(z) = f(0)\\prod_{n=1}^{\\infty} (1+\\epsilon_nz^n)^{\\alpha_n}$ for every $z \\in D$. From this representation we obtain a numerical method for calculating products of the form $\\prod_{p \\text{prime}} f(1/p)$ provided $f(0)=1$ and $f'(0) = 0$; our method generalizes a well known method of Pieter Moree. We illustrate this method on a constant of Ramanujan $\\pi^{-1/2}\\prod_{p \\text{prime}} \\sqrt{p^2-p}\\ln(p/(p-1))$. From the properties of the exponents $\\alpha_n$, we obtain a proof of the following congruences, which have been the subject of several recent publications motivated by some questions of Arnold: for every $n \\times n$ integral matrix $A$, every prime number $p$, and every positive integer $k$ we have $\\text{tr} A^{p^k} \\equiv \\text{tr} A^{p^{k-1}} (\\text{mod}\\,{p^k})$.", "revisions": [ { "version": "v3", "updated": "2012-04-04T03:35:16.000Z" } ], "analyses": { "subjects": [ "11Y60", "30E10", "30J99", "40A30", "40A20", "11A07", "11C20" ], "keywords": [ "analytic function", "infinite products", "numerical computations", "representation", "application" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.1335M" } } }