All open problems
Source labels openChecked July 26, 2026

OEISNumber theory

Numbers $n$ such that $n^2 + \pi(n)$ is prime.: Infinite

Conjecture: the sequence A228828 is infinite.

Mathematical statement

Conjecture: the sequence A228828 is infinite.

Statement source: OEIS 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

a.infinite

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem a.infinite : {a n | n}.Infinite := 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