2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/74473Let n(2,k) denote the largest integer n for which there exists a set A of k nonnegative integers such that the sumset 2A contains {0,1,2,...,n-1}. A classical problem in additive number theory is to find an upper bound for n(2,k). In this paper it is proved that limsup_{k\to\infty} n(2,k)/k^2 \leq 0.4789.19 pages; LaTexNumber TheoryCombinatorics11B13text