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Erdős problem 90

Conjectured upper bound on how many pairs among nn points in the plane can be exactly one unit apart.

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90.lean

Retained formal statement2 of 8

Constructive form of the disproof. There is an absolute constant c>0c > 0 such that infinitely many nn admit a configuration realising at least n1+cn^{1+c} unit distances.

This is the qualitative content of Theorem 1.1 of Alon–Bloom–Gowers–Litt–Sawin–Shankar– Tsimerman–Wang–Matchett Wood, [*Remarks on the disproof of the unit distance conjecture*](https://arxiv.org/abs/2605.20695) (2026). An explicit bound c0.014114c \ge 0.014114 is given by Sawin, [*An explicit lower bound for the unit distance problem*](https://arxiv.org/abs/2605.20579) (2026); see erdos_90.variants.sawin_explicit below.

FormalConjectures/ErdosProblems/90.leanErdos90.erdos_90.variants.polynomial_lower_bound1 lineExact file
c > 0, {n | ↑n ^ (1 + c) ≤ ↑(Erdos90.maxUnitDistances n)}.Infinite
SolvedStatement only, no proof

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