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Source labels openChecked July 26, 2026

Written on the Wall IICombinatorics

Written on the Wall II - Conjecture 141

Mathematical statement

WOWII Conjecture 141

For a simple connected graph G, tree(G) ≥ ⌊girth(G) / 2⌋ - 1 + max_v l(v) where tree(G) is the number of vertices of a largest induced tree subgraph, girth(G) is the length of the shortest cycle (0 if acyclic), and l(v) = indepNeighbors G v is the independence number of the neighbourhood of v.

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

conjecture141

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem conjecture141 (G : SimpleGraph α) [DecidableRel G.Adj] (h : G.Connected) :    (G.girth / 2 : ) - 1 + ((Finset.univ.sup (indepNeighborsCard G) : ) : )     (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