{ "id": "math/0302091", "version": "v2", "published": "2003-02-10T19:05:23.000Z", "updated": "2003-12-03T19:11:11.000Z", "title": "Every function is the representation function of an additive basis for the integers", "authors": [ "Melvyn B. Nathanson" ], "comment": "15 pages. LaTex file. Corrected and revised manuscript", "categories": [ "math.NT", "math.CO" ], "abstract": "Let A be a set of integers. For every integer n, let r_{A,h}(n) denote the number of representations of n in the form n = a_1 + a_2 + ... + a_h, where a_1, a_2,...,a_h are in A and a_1 \\leq a_2 \\leq ... \\leq a_h. The function r_{A,h}: Z \\to N_0 \\cup \\infty is the representation function of order h for A. The set A is called an asymptotic basis of order h if r_{A,h}^{-1}(0) is finite, that is, if every integer with at most a finite number of exceptions can be represented as the sum of exactly h not necessarily distinct elements of A. It is proved that every function is a representation function, that is, if f: Z \\to N_0 \\cup \\infty is any function such that f^{-1}(0) is finite, then there exists a set A of integers such that f(n) = r_{A,h}(n) for all n in Z. Moreover, the set A can be arbitrarily sparse in the sense that, if \\phi(x) \\to \\infty, then there exists a set A with f(n) = r_{A,h}(n) such that card{a in A : |a| \\leq x} < \\phi(x) for all sufficiently large x.", "revisions": [ { "version": "v2", "updated": "2003-12-03T19:11:11.000Z" } ], "analyses": { "subjects": [ "11B13", "11B34", "11B05" ], "keywords": [ "representation function", "additive basis", "asymptotic basis", "finite number", "necessarily distinct elements" ], "note": { "typesetting": "LaTeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2003math......2091N" } } }