1 citations · 2 across the 5 of their papers we have counts for
5 papers
Provable better quasi orders
Anton Freund, Alberto Marcone, Fedor Pakhomov +1
It has recently been shown that fairly strong axiom systems such as cannot prove that the antichain with three elements is a better quasi order (). I…
Weak well orders and Fraïssé's conjecture
Anton Freund, Davide Manca
The notion of well order admits an alternative definition in terms of embeddings between initial segments. We use the framework of reverse mathematics to investigate the logical st…
The logical strength of minimal bad arrays
Anton Freund, Fedor Pakhomov, Giovanni Soldà
This paper studies logical aspects of the notion of better quasi order, which has been introduced by C. Nash-Williams (Mathematical Proceedings of the Cambridge Philosophical Socie…
The uniform Kruskal theorem: between finite combinatorics and strong set existence
Anton Freund, Patrick Uftring
The uniform Kruskal theorem extends the original result for trees to general recursive data types. As shown by A. Freund, M. Rathjen and A. Weiermann, it is equivalent to -c…
Well ordering principles for iterated -comprehension
Anton Freund, Michael Rathjen
We introduce ordinal collapsing principles that are inspired by proof theory but have a set theoretic flavor. These principles are shown to be equivalent to iterated -compre…