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Source labels openChecked July 26, 2026

Erdős ProblemsCombinatorics

Erdős Problem 85

Is it true that, for all large nn, f(n+1)f(n)f(n + 1) \ge f(n)?

Mathematical statement

Is it true that, for all large nn, f(n+1)f(n)f(n + 1) \ge f(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

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_85

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_85 : answer(sorry)  ᶠ n in atTop, f n  f (n + 1) := 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