VibeMathedMath problems solved with AI

The Alon-Krivelevich-Sudakov conjecture: graphs with a fixed forbidden subgraph have chromatic number O(Delta/log Delta)

Every graph of maximum degree Δ\Delta has χ(G)≤Δ+1\chi(G)\le\Delta+1. Johansson (1996) proved χ(G)=O(Δ/log⁡Δ)\chi(G)=O(\Delta/\log\Delta) for triangle-free graphs, and Alon, Krivelevich and Sudakov (1999) extended this to graphs with sparse neighborhoods. For general fixed FF, and already for F=K4F=K_4, the best bounds carried an extra log⁡log⁡Δ\log\log\Delta factor. Alon, Krivelevich and Sudakov (1999, Conjecture 3.1) conjectured: for every fixed graph FF there is CFC_F such that every FF-free graph of maximum degree Δ\Delta has chromatic number at most CFΔ/log⁡ΔC_F\Delta/\log\Delta. Is this true?

Result
Proved(see note)
Status
Candidate (review pending)
AI contribution
AI-discovered
Method
Argument
Field
Graph coloring: sparse and F-free graphs
Posed by
N. Alon, M. Krivelevich and B. Sudakov, Coloring graphs with sparse neighborhoods, J. Combin. Theory Ser. B 77 (1999), Conjecture 3.1
Year posed
1999
Years open
27y
Solved
2026-10-05
Model
Unreleased internal OpenAI model
Vendor
OpenAI
Collaborators
—
Verification
Unreviewed
Publication
Announced
Collection
OpenAI math release (October 2026), version adc7f12
Significance
42 / 100
Disclosed cost
—
Wikipedia
No dedicated article

What was actually shown

Theorem 1.1: for every r≥4r\ge4 there are CrC_r and Δr\Delta_r such that every KrK_r-free graph of maximum degree Δ≥Δr\Delta\ge\Delta_r has correspondence (DP) chromatic number at most ⌈CrΔ/log⁡Δ⌉\lceil C_r\Delta/\log\Delta\rceil; Corollary 1.2 gives the same for any fixed forbidden subgraph FF, which implies the conjecture for ordinary and list coloring. The proof is a round-based random partial coloring with weighted lists, controlled by an entropy potential and local adjustments that offset triangle correlations. Constants and thresholds are not optimized; no explicit leading constant is claimed.

What the AI did

The OpenAI math release (github.com/openai/math, commit adc7f12) states that its results were produced by an unreleased internal OpenAI model under one fixed procedure, averaging about three hours of ChatGPT Pro thinking compute per result. This result is not among the README's stated exceptions (the Re(s) > 11/12 zero-free region write-up and the Hodge conjecture for CM abelian varieties). The manuscript is credited to OpenAI alone and names no human author. The manuscript states that it develops the multiplier and entropy-splitting methods of its companion on the AEKS independence conjecture (25 September 2026) and proves all ingredients itself.

Verification

No independent mathematician has checked this yet. Checked here: the abstract, introduction, Theorem 1.1 and Corollary 1.2 of the TeX source, read against Conjecture 3.1 of Alon, Krivelevich and Sudakov as the manuscript cites it; the proof was not refereed. The family's Lean material (lean/docs/184.md) formalizes only the companion independence bound, not this coloring theorem, so this entry is unreviewed.

Sources

Changelog1 change

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