Pan galactic division (Q906021)

This expository paper simplifies a proof of the following result from set theory: let \(A\) and \(B\) be sets and \(n\geq 1\) natural, such that there is an injective map from \(A \times \{0, \dots ,n\}\) into \(B \times \{0,\dots ,n\}\); then there is an injection from \(A\) into \(B\).