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Source labels openChecked July 26, 2026

PapersCombinatorics

Kotzig's Conjecture

For any tree TT with nn edges, the complete graph K2n+1K_{2n+1} decomposes into 2n+12n+1 edge-disjoint copies of TT via cyclic shifts of a single embedding.

Mathematical statement

For any tree TT with nn edges, the complete graph K2n+1K_{2n+1} decomposes into 2n+12n+1 edge-disjoint copies of TT via cyclic shifts of a single embedding.

The 2n+12n+1 copies are f0,f1,,f2nf_0, f_1, \dots, f_{2n} where fi(v)=f0(v)+if_i(v) = f_0(v) + i for all vertices vv , each copy is obtained by adding i(mod2n+1)i \pmod{2n+1} to every vertex of the base copy. This is strictly stronger than RingelConjecture.ringel_conjecture.

Statement source: Papers 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

kotzig_conjecture

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem kotzig_conjecture {V : Type} [Finite V]    (T : SimpleGraph V) (hT : T.IsTree)    (n : ) (hn : T.edgeSet.ncard = n) :     f : Fin (2 * n + 1)  (V ↪ Fin (2 * n + 1)),      ( i v, f i v = f 0 v + i)       Pairwise (fun i j => Disjoint (T.map (f i)).edgeSet (T.map (f j)).edgeSet)       ⨆ i, T.map (f i) = (⊤ : SimpleGraph (Fin (2 * n + 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