Erdős problem 428Is there a set A⊆NA\subseteq \mathbb{N} such that, for infinitely many nn, all of n−an-a are prime for all a∈Aa\in A with 0<a<n0 < a < n and lim inf∣A∩[1,x]∣π(x)>0?\liminf\frac{\lvert A\cap [1,x]\rvert}{\pi(x)}>0?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 4282 retained source recordsCanvaspublic previewSource#428→ResultNone→Checks0