Erdős problem 257Let A⊆NA\subseteq\mathbb{N} be an infinite set. Is ∑n∈A12n−1 \sum_{n\in A} \frac{1}{2^n - 1} irrational?WorkspaceContinue locallyOpen sourceSign in to contributeOpen this exact Problem, source revision, and authority Repository in Workbench. This handoff does not clone, switch, upload, or execute anything.FilesErdős problem 2574 retained source recordsCanvaspublic previewSource#257→ResultNone→Checks0