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Erdős problem 498

Let z1,…,zn∈Cz_1,\ldots,z_n\in\mathbb{C} with 1≤∣zi∣1\leq \lvert z_i\rvert for 1≤i≤n1\leq i\leq n. Let DD be an arbitrary disc of radius 11. Is it true that the number of sums of the shape ∑i=1nϵizi for ϵi∈{−1,1}\sum_{i=1}^n\epsilon_iz_i \textrm{ for }\epsilon_i\in \{-1,1\} which lie in DD is at most (n⌊n/2⌋)\binom{n}{\lfloor n/2\rfloor}?

No current result

No reviewed Result is current in Vela Mathematics Program. Retained source material is shown below.

Retained declaration

FormalConjectures/ErdosProblems/498.lean

Formal Conjectures

FormalConjectures/ErdosProblems/498.leanErdos498.erdos_4985 linesExact file
True ↔  ∀ (n : ℕ) (z : Fin n → ℂ),    (∀ (i : Fin n), 1 ≤ ‖z i‖) →      ∀ (c : ℂ),        {ε | (∀ (i : Fin n), ε i = -1 ∨ ε i = 1) ∧ ∑ i, ↑(ε i) * z i ∈ Metric.ball c 1}.ncard ≤ n.choose (n / 2)
SolvedStatement only, no proof

Proof manifests naming this Problem

  • Jayyhk Erdős Leanjayyhk:erdos:498
  • PLBY Lean proofsErdosProblems.Erdos498

Reported activity

Reported by these sources. Not reviewed here.

  • Formalization

    Erdős AI contributions wiki · Jan 27, 2026

    Machine
    Aristotle, Claude Opus, Gemini Flash, Gemini Pro
    Open the source record

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