All open problems
Source labels openChecked July 26, 2026

Millennium ProblemsGeneral topology

Poincare: Smooth Other Cases

It is conjectured that the only values of n>4n > 4 for which the smooth version of the conjecture holds are n=5,6,12,56,61n = 5, 6, 12, 56, 61. See Conjecture 1.17 in [Wang2017].

Mathematical statement

It is conjectured that the only values of n>4n > 4 for which the smooth version of the conjecture holds are n=5,6,12,56,61n = 5, 6, 12, 56, 61. See Conjecture 1.17 in [Wang2017].

Statement source: Millennium 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

poincare_conjecture.variants.smooth_other_cases

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem poincare_conjecture.variants.smooth_other_cases (n : ) (hn : n > 4)    (hn' : n  SmoothTrueValues) : ¬ SmoothConjectureFor n := 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