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Source labels openChecked July 26, 2026

WikipediaNumber theory

Andrica's conjecture

Andrica's conjecture* The inequality pn+1pn<1\sqrt{p_{n+1}}-\sqrt{p_n} < 1 holds for all nn, where pnp_n is the nn-th prime number.

Mathematical statement

Andrica's conjecture* The inequality pn+1pn<1\sqrt{p_{n+1}}-\sqrt{p_n} < 1 holds for all nn, where pnp_n is the nn-th prime number.

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

andrica_conjecture

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem andrica_conjecture (n : ) :    Real.sqrt ((n+1).nth Nat.Prime) - Real.sqrt (n.nth Nat.Prime) < 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