3 problems

Let $P$ be a bqo, and consider bqo-preserving operators such as $P\mapsto P^n$ for fixed $n$ and $P\mapsto T(P)$, where $T(P)$ is the Kruskal ordering. The structure of the iterate…

Let $[\omega]^2_+$ denote the relevant domain of ordered pairs of natural numbers, let $C([\omega]^2_+,\mathbb{Q})$ be the space of continuous functions from this domain to…

Countable-union conjecture. Every well-quasi-ordered poset is a countable union of better quasi-orders.