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Source labels openChecked July 26, 2026

Written on the Wall IICombinatorics

Written on the Wall II - Conjecture 198a

Mathematical statement

WOWII Conjecture 198a

For a simple connected graph G, if b(G) ≤ 2 + ecc_avg(G), then G has a Hamiltonian path. Here b(G) is the number of vertices in a largest induced bipartite subgraph, and ecc_avg(G) is the average eccentricity of G. A Hamiltonian path is a walk visiting every vertex exactly once.

Statement source: Written on the Wall II 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

conjecture198a

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem conjecture198a (G : SimpleGraph α) (h : G.Connected)    (hb : b G  2 + averageEccentricity G) :     a b : α,  p : G.Walk a b, p.IsHamiltonian := 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