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arXiv · 1411.6963

On certain quaternary quadratic forms

Kazuhide Matsuda
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Abstract

In this paper, we determine all the positive integers $a, b$ and $c$ such that every nonnegative integer can be represented as $$ f^{a,b}_c(x,y,z,w)=ax^2+by^2+c(z^2+zw+w^2) \,\, \textrm{with} \,\,x,y,z,w\in\mathbb{Z}. $$ Furthermore, we prove that $f^{a,b}_c$ can represent all the nonnegative integers if it represents $n=1,2,3,5,6,10.$

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Kazuhide Matsuda. 2014-11-14. On certain quaternary quadratic forms. https://arxiv.org/abs/1411.6963

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