T Kowalczyk, J Vill - arXiv preprint arXiv:2311.07356, 2023 - arxiv.org
We show that the higher Pythagoras numbers for the polynomial ring are infinite $ p_ {2s}(K
[x_1, x_2,\dots, x_n])=\infty $ provided that $ K $ is a real field, $ n\geq2 $ and $ s\geq 1 …