Lee, Chan Lye; Lim, Chia S. A postage problem. (English) Zbl 1250.97004 Menemui Mat. 27, No. 2, 27-29 (2005). Summary: Let \(a\) and \(b\) be two positive integers greater than 1. Suppose that \(a\) and \(b\) are relatively prime. Then, there exists a positive integer \(N\) such that for all integers \(n\geq N\), there exist nonnegative integers \(x\) and \(y\) such that \(n = ax + by\). Furthermore, it is not possible to find nonnegative integers for \(x\) and \(y\) such that \(N -1=ax+by\). Cited in 1 Document MSC: 97F60 Number theory (educational aspects) 11D04 Linear Diophantine equations 97N70 Discrete mathematics (educational aspects) Keywords:Diophantine equations; greatest common divisors; number theory; discrete mathematics; modular arithmetic PDFBibTeX XMLCite \textit{C. L. Lee} and \textit{C. S. Lim}, Menemui Mat. 27, No. 2, 27--29 (2005; Zbl 1250.97004)