{ "id": "2203.12901", "version": "v1", "published": "2022-03-24T07:38:22.000Z", "updated": "2022-03-24T07:38:22.000Z", "title": "Transcendence and continued fraction expansion of values of Hecke-Mahler series", "authors": [ "Yann Bugeaud", "Michel Laurent" ], "comment": "29 pages", "categories": [ "math.NT" ], "abstract": "Let $\\theta$ and $\\rho$ be real numbers with $0 \\le \\theta, \\rho < 1$ and $\\theta$ irrational. We show that the Hecke-Mahler series $$ F_{\\theta, \\rho} (z_1, z_2) = \\sum_{k_1 \\ge 1} \\, \\sum_{k_2 = 1}^{\\lfloor k_1 \\theta + \\rho \\rfloor} \\, z_1^{k_1} z_2^{k_2}, $$ where $\\lfloor \\cdot \\rfloor$ denotes the integer part function, takes transcendental values at any algebraic point $(\\beta, \\alpha)$ with $0 < |\\beta|, |\\beta \\alpha^\\theta | < 1$. This extends earlier results of Mahler (1929) and Loxton and van der Poorten (1977), who settled the case $\\rho=0$. Furthermore, for positive integers $b$ and $a$, with $b \\ge 2$ and $a$ congruent to $1$ modulo $b-1$, we give the continued fraction expansion of the number $$ {(b-1)^2\\over b} F_{\\theta, \\rho} \\left({1\\over b}, {1\\over a}\\right)+{\\lfloor \\theta+\\rho\\rfloor(b-1)\\over b^2a}, $$ from which we derive a formula giving the irrationality exponent of $F_{\\theta, \\rho} (1/b, 1/a)$.", "revisions": [ { "version": "v1", "updated": "2022-03-24T07:38:22.000Z" } ], "analyses": { "subjects": [ "11J04", "11J70", "11J81" ], "keywords": [ "continued fraction expansion", "hecke-mahler series", "transcendence", "extends earlier results", "integer part function" ], "note": { "typesetting": "TeX", "pages": 29, "language": "en", "license": "arXiv", "status": "editable" } } }