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arXiv · 2306.05959

On the Pythagoras number for polynomials of degree 4 in 5 variables

Santiago Laplagne
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Abstract

We give an example of a polynomial of degree 4 in 5 variables that is the sum of squares of 8 polynomials and cannot be decomposed as the sum of 7 squares. This improves the current existing lower bound of 7 polynomials for the Pythagoras number $p(5,4)$.

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Santiago Laplagne. 2023-06-09. On the Pythagoras number for polynomials of degree 4 in 5 variables. https://arxiv.org/abs/2306.05959

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