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Regressive Ramsey numbers are Ackermannian

Menachem Kojman·Saharon Shelah
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Abstract

We give an elementary proof of the fact that regressive Ramsey numbers are Ackermannian. This fact was first proved by Kanamori and McAloon with mathematical logic techniques.

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Menachem Kojman, Saharon Shelah. 1998-05-15. Regressive Ramsey numbers are Ackermannian. https://arxiv.org/abs/math/9805150

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