The Ajtai–Erdős–Komlós–Szemerédi independence conjecture
Appearance
The Ajtai–Erdős–Komlós–Szemerédi (AEKS) independence conjecture (1981; Erdős Problem 802) asserts the following for every fixed r. Every Kr-free graph on n vertices with average degree d has an independent set of size at least a constant (depending on r) times n log d/d. That is the same order as for triangle-free graphs. Two manuscripts in OpenAI's public mathematics collection (github.com/openai/math) make claims on this problem and on the related Alon–Krivelevich–Sudakov coloring conjecture. This page summarizes the published claims and lists publicly available follow-up work.
Background
- As recounted in the introduction of A logarithmic independence bound for clique-free graphs:
- For general graphs the bound α(G) ≥ n/(d + 1) is best possible, as disjoint unions of cliques show.
- Ajtai, Komlós and Szemerédi (1980) proved the logarithmic improvement for triangle-free graphs, and Shearer (1983) obtained the asymptotic coefficient 1.
- In 1981, Ajtai, Erdős, Komlós and Szemerédi conjectured the same order of growth for each fixed forbidden clique. They proved the lower bound Ωr(n log log d/d).
- Shearer (1995) improved this to Ωr(n log d/(d log log d)). Later refinements describe more of the local structure and, for a fixed forbidden clique, retain a log log loss: Dutta–Mubayi–Subramanian; Davies–Kang–Pirot–Sereni; Dhawan.
- Logarithmic bounds hold under stronger local assumptions, for example Alon (1996), when every vertex neighbourhood is (r − 2)-colourable.
- The Erdős Problems page for problem 802 records the conjecture and the bounds of Ajtai–Erdős–Komlós–Szemerédi, Shearer, Ajtai–Komlós–Szemerédi and Alon.
The original results
- Independence (25 September 2026). The manuscript A logarithmic independence bound for clique-free graphs, Theorem 1.1: for every integer r ≥ 4 there is cr > 0 such that every finite simple Kr-free graph with n vertices and average degree d ≥ 2 satisfies α(G) ≥ cr n log d/d.
- The manuscript states that this gives a positive answer to the AEKS conjecture, recorded as Erdős Problem 802. The order is best possible up to a constant even for triangle-free graphs, and the constant cr is not optimized.
- Coloring (5 October 2026). The manuscript Correspondence coloring graphs with a forbidden clique claims a bound for every fixed r ≥ 4: every Kr-free graph of sufficiently large maximum degree Δ has correspondence chromatic number Or(Δ/log Δ).
- It presents this as resolving the Alon–Krivelevich–Sudakov coloring conjecture in the stronger correspondence-coloring form.
- The same bound, with a constant depending on F, is claimed when any fixed graph F is excluded as a subgraph. Ordinary and list coloring satisfy the same bounds.
- Sources. Commit
1581d4cof the openai/math repository: - Formalization, as described by the repository.
- The scope note lean/docs/184.md links only the independence manuscript. It states the formalized result: for every fixed integer r ≥ 4 there is cr > 0 such that every finite Kr-free simple graph on n vertices with average degree d ≥ 2 has an independent set of size at least cr n log d/d.
- The Comparator challenge CliqueFreeLog.lean states
logarithmic_independence_bound, with the average degree defined as 2|E|/|V| and Mathlib's independence number. - The coloring result is not among the selected statements.
Public follow-up work
| Date | Work | Relation | Public claim | Public status (checked 17 October 2026) |
|---|---|---|---|---|
| 2026-10-08 | MathVet (GitHub; review of openai/math, tables at repository commit c76f1e4, 14 October 2026) |
Review (fidelity of the formal statements) | Rates the family "partial". Only the independence half is stated; the coloring conjecture in correspondence-coloring form has no Lean statement. Records a sandboxed Comparator pass for CliqueFreeLog. |
MathVet states that it does not claim any theorem false and reports what was machine-checked as stated. |
| 2026-10-10 to 2026-10-14 | con-leche development journal (task #348) | Verification (second kernel) | In its run over all Comparator challenges of the collection at commit fd4aeeb, the journal's table of exceptions (time-outs, fuel, memory, errors) does not list CliqueFreeLog. The challenge was therefore accepted by con-leche and by Lean's official kernel. |
Development journal. |
| 2026-10-10 | cert-machine, openai/math lane K, run 38017370880 | Verification (two kernels) | Records that Lean's default kernel and the nanoda kernel accept the CliqueFreeLog solution (251 s). The project reports two-kernel certification of 398 of 416 challenges of the collection. |
Repository. |
| 2026-10-11 | Formal Conjectures pull request #7165 | Catalogue (formal statements) | Adds Erdős Problem 802 with the research status "open", following the Erdős Problems page, together with the known bounds of Ajtai–Erdős–Komlós–Szemerédi, Shearer, Ajtai–Komlós–Szemerédi and Alon tagged as solved. | Open. |
| 2026-10-11 | K. Chen, arXiv:2610.15293v1, A note on the logarithmic exponent of Ramsey number r(4,t) | Uses | Combines recent lower bounds for the off-diagonal Ramsey numbers r(s, t) with fixed s ≥ 5 (citing preprints of the collection) with the recent proof of the AEKS independence conjecture. It deduces r(4, t) = t3/(log t)2+o(1). The note is "solely for informal circulation and will not be submitted for publication". | arXiv preprint (v1). |
Notes
- The kernel checks listed above concern the formal statement
logarithmic_independence_boundas written; the coloring result has no formal statement in the collection. - As of the date above, the Erdős Problems page for problem 802 (last edited 26 October 2025) lists no proof claims.
- The list covers follow-ups found in public sources up to the date above; it is not a priority or completeness claim.