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Source labels openChecked July 26, 2026

Erdős ProblemsCombinatorics

Erdős Problem 653

Let x1,,xnR2x_1,\ldots,x_n\in \mathbb{R}^2 and let R(xi)=#{xjxi:ji}R(x_i)=\#\{ \lvert x_j-x_i\rvert : j\neq i\}, where the points are ordered such that R(x1)R(xn).R(x_1)\leq \cdots \leq R(x_n). Let g(n)g(n) be the maximum number of distinct values the R(xi)R(x_i) can take. Is it true that...

Mathematical statement

Let x1,,xnR2x_1,\ldots,x_n\in \mathbb{R}^2 and let R(xi)=#{xjxi:ji}R(x_i)=\#\{ \lvert x_j-x_i\rvert : j\neq i\}, where the points are ordered such that R(x1)R(xn).R(x_1)\leq \cdots \leq R(x_n). Let g(n)g(n) be the maximum number of distinct values the R(xi)R(x_i) can take. Is it true that g(n)(1o(1))ng(n) \geq (1-o(1))n?

Statement source: Erdős Problems statement material

Statement terms: Source-specific

Source-specific terms. Therefore does not assert reuse rights beyond attributed display.

Statement artifacts, not proofs

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Pinned Lean formulation 1

erdos_653

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_653 : answer(sorry)   o :   , o =o[atTop] (1 :   )     ᶠ n in atTop, (1 - o n) * n  maximalDistinctDistancesFrom n := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References