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Černý Conjecture

Černý Conjecture*: Every synchronizing DFA with nn states admits a synchronizing word of length at most (n1)2(n - 1)^2.

Mathematical statement

Černý Conjecture*: Every synchronizing DFA with nn states admits a synchronizing word of length at most (n1)2(n - 1)^2.

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

cerny_conjecture

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem cerny_conjecture :    answer(sorry)   {α : Type*} {σ : Type*} [Fintype σ] (M : DFA α σ) (hM : M.IsSynchronizing) ,     w : List α, M.IsSynchronizingWord w  w.length  (Fintype.card σ - 1)^2 := 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