K. Yokoyama

activity

20132023

most citedThe proof-theoretic strength of Ramsey's theorem for pairs and two colors

8 citations · 19 across the 21 of their papers we have counts for

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Showing 2021Show all

2 papers · 1 filter

math.LO2021

An isomorphism theorem for models of Weak König's Lemma without primitive recursion

Marta Fiori-Carones, Leszek Aleksander Kołodziejczyk, Tin Lok Wong +1

We prove that if $(M, X)$ and $(M, Y)$ are countable models of the theory $WKL_{0}^{*}$ such that $I Σ_{1} (A)$ fails for some $A \in \mathcal{X} \cap \…

math.LO2021

Very weak fragments of weak Kőnig's lemma

Stephen G. Simpson, Keita Yokoyama

It is well-known that any finite $Π_{1}^{0}$ -class of $2^{N}$ has a computable member. Then, how can we understand this in the context of reverse mathematics? In this note,…