All open problems
Source labels openChecked July 26, 2026

Erdős ProblemsNumber theory

Erdős Problem 885

Is it true that, for every k1k \geq 1, there exist integers N1<<NkN_1 < \dots < N_k such that iD(Ni)k|\cap_i D(N_i)| \geq k?

Mathematical statement

Is it true that, for every k1k \geq 1, there exist integers N1<<NkN_1 < \dots < N_k such that iD(Ni)k|\cap_i D(N_i)| \geq k?

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

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

erdos_885

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_885 : answer(sorry)   k  1,     Ns : Finset ,      ( n  Ns, 1  n)       Ns.card = k       (⋂ n  Ns, factorDifferenceSet n).ncard  k := 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