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arXiv · 2011.13722

Rado equations solved by linear combinations of idempotent ultrafilters

Lorenzo Luperi Baglini·Paulo Henrique Arruda
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Abstract

We fully characterise the solvability of Rado equations inside linear combinations $a_{1}\U\oplus\dots\oplus a_{n}\U$ of idempotent ultrafilters $\U\inβ\Z$ by exploiting known relations between such combinations and strings of integers. This generalises a partial characterization previously obtained by Mauro Di Nasso.

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Lorenzo Luperi Baglini, Paulo Henrique Arruda. 2021-11-03. Rado equations solved by linear combinations of idempotent ultrafilters. https://doi.org/10.1016/j.topol.2021.107897

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