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arXiv · 0909.1666

On Sets of Integers where Each Pair Sums to a Square

Allan J. MacLeod
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Abstract

We discuss the problem of finding distinct integer sets $\{x_1,x_2,...,x_n\}$ where each sum $x_i+x_j, i \ne j$ is a square, and $n \le 7$. We confirm minimal results of Lagrange and Nicolas for $n=5$ and for the related problem with triples. We provide new solution sets for $n=6$ to add to the single known set. This provides new information for problem D15 in Guy's {\it Unsolved Problems in Number Theory}

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Allan J. MacLeod. 2009-09-09. On Sets of Integers where Each Pair Sums to a Square. https://arxiv.org/abs/0909.1666

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