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Question: Is the following statement true?
Statement: Let $a, b \ge 1$ be coprime numbers. Then $\exists N \ge 0 $ $\forall n \ge N$ $\exists u, v \ge 0$ with $n=au+bv$.
Let $N(a,b)$ be the smallest possible $N$. Then $N(a,b) = (a-1)(b-1)$.