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

Authors

  • Santiago Laplagne Instituto de Cálculo, FCEN, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón I, C1428EGA Buenos Aires, Argentina

DOI:

https://doi.org/10.33044/revuma.4224

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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References

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Published

2025-06-30

Issue

Vol. 68 No. 1 (2025)

Section

Article

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Copyright (c) 2025 Santiago Laplagne

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