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Reed's omega, delta, and chi conjecture

For a finite graph GG, we define Δ(G)\Delta(G) to be the maximum degree, ω(G)\omega(G) to be the size of the largest clique subgraph, and χ(G)\chi(G) to be the chromatic number. Reed's omega, delta, and chi conjecture states that $$\chi(G) \leq \lceil \frac{1}{2...

Mathematical statement

For a finite graph GG, we define Δ(G)\Delta(G) to be the maximum degree, ω(G)\omega(G) to be the size of the largest clique subgraph, and χ(G)\chi(G) to be the chromatic number. Reed's omega, delta, and chi conjecture states that χ(G)12(ω(G)+Δ(G)+1).\chi(G) \leq \lceil \frac{1}{2}(\omega(G) + \Delta(G) + 1) \rceil.

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

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Pinned Lean formulation 1

reed_omega_delta_chi_conjecture_for_finite_graphs

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem reed_omega_delta_chi_conjecture_for_finite_graphs :   {V : Type} [Fintype V] [DecidableEq V] (G : SimpleGraph V) [DecidableRel G.Adj],    let χ := G.chromaticNumber    let ω := G.cliqueNum    let Δ := G.maxDegree    2 * χ  ω + Δ + 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