Erdős Problem #675

`IsTranslation A n t` says that \(t \geq 1\) and, for all \(1 \leq a \leq n\), \(a \in A\) if and only if \(a + t \in A\).

A set \(A \subseteq \mathbb{N}\) has the translation property if, for every \(n\), there is an integer \(t_n \geq 1\) such that, for all \(1 \leq a \leq n\), \(a \in A\) if and only if \(a + t_n \in A\).

`minTranslation A n` is the least \(t_n \geq 1\) such that, for all \(1 \leq a \leq n\), \(a \in A\) if and only if \(a + t_n \in A\). It is `0` if there is no such \(t_n\).