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arXiv · 1909.04982

A sum of three nonunit squares of integers

Daejun Kim·Jeongwon Lee·Byeong-Kweon Oh
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Abstract

We say a positive integer is a sum of three nonunit squares if it is a sum of three squares of integers other than one. In this article, we find all integers which are sums of three nonunit squares assuming that the Generalized Riemann Hypothesis(GRH) holds. As applications, we find all integers, under the GRH only when $k=3$, which are sums of $k$ nonzero triangular numbers, sums of $k$ nonzero generalized pentagonal numbers, and sums of $k$ nonzero generalized octagonal numbers, respectively for any integer $k\ge 3$.

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Daejun Kim, Jeongwon Lee, Byeong-Kweon Oh. 2019-09-11. A sum of three nonunit squares of integers. https://arxiv.org/abs/1909.04982

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