New parametrization of $A^2+B^2+C^2=3D^2$ and Lagrange's four-square theorem

Eugen J. Ionascu

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arXiv · 1411.6306

New parametrization of $A^2+B^2+C^2=3D^2$ and Lagrange's four-square theorem

Eugen J. Ionascu

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Abstract

In this paper we provide a new parametrization for the diophantine equation $A^2+B^2+C^2=3D^2$ and give a series of corollaries. We discuss some connections with Lagrange's four-square theorem. As applications, we find new parameterizations of equilateral triangles and regular tetrahedrons having integer coordinates in three dimensions.

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Eugen J. Ionascu. 2014-11-23. New parametrization of $A^2+B^2+C^2=3D^2$ and Lagrange's four-square theorem. https://arxiv.org/abs/1411.6306

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