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Source labels openChecked July 26, 2026

Written on the Wall IICombinatorics

Written on the Wall II - Conjecture 144

Mathematical statement

WOWII Conjecture 144

For a simple connected graph GG, tree(G)girth(G)1+ecc(Centers)\mathrm{tree}(G) \ge \mathrm{girth}(G) - 1 + \mathrm{ecc}(\mathrm{Centers}) where tree(G)\mathrm{tree}(G) is the largest induced tree size, girth(G)\mathrm{girth}(G) is the length of the shortest cycle (00 if acyclic), Centers=G.center\mathrm{Centers} = G.\mathrm{center} is the set of vertices with minimum eccentricity (the center of GG), and ecc(Centers)\mathrm{ecc}(\mathrm{Centers}) is the eccentricity of the center set , the maximum distance from any non-center vertex to the nearest center vertex.

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

conjecture144

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem conjecture144 (G : SimpleGraph α) (h : G.Connected) :    (G.girth : ) - 1 + (ecc G G.center : )  (largestInducedTreeSize G : ) := 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