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Source labels openChecked July 26, 2026

WikipediaNumber theory

Oppermann's Conjecture: Ii

For every integer x2x \ge 2 there exists a prime between x2x^2 and x(x+1)x(x+1).

Mathematical statement

For every integer x2x \ge 2 there exists a prime between x2x^2 and x(x+1)x(x+1).

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

Attributed source material. Reuse must follow the linked attribution and share-alike terms.

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

oppermann_conjecture.parts.ii

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem oppermann_conjecture.parts.ii (x : ) (hx : 2  x) :     p  Ioo (x^2) (x * (x + 1)), p.Prime := 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