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arXiv · 2412.16740

Hilbert's tenth problem for systems of diagonal quadratic forms, and B\"{u}chi's problem

Stanley Yao Xiao
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Abstract

In this paper we complete B\"{u}chi's proof that there is no decision algorithm for the solubility in integers of arbitrary systems of diagonal quadratic form equations, by proving the assertion that whenever $x_1^2, \cdots, x_5^2$ are five squares such that the second differences satisfy \[x_{k+2}^2 - 2 x_{k+1}^2 + x_k^2 = 2\] for $k = 1,2,3$, then they must be consecutive. This answers a question of J.~Richard~B\"{u}chi.

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Stanley Yao Xiao. 2024-12-21. Hilbert's tenth problem for systems of diagonal quadratic forms, and B\"{u}chi's problem. https://arxiv.org/abs/2412.16740

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