Written on the Wall II, Graph Conjecture 109
Must every connected graph satisfy the proposed upper bound on its independence number in terms of residue and largest induced-bipartite-subgraph order? The family violates it for every .
- Result
- Disproved
- Status
- Resolved
- AI contribution
- AI-discovered
- Method
- Construction
- Field
- Graph invariants
- Posed by
- Graffiti (Written on the Wall II)
- Year posed
- 1996
- Years open
- 30y
- Solved
- 2026-07-28
- Model
- GPT-5.6 Sol Max (Codex)
- Vendor
- OpenAI
- Collaborators
- —
- Verification
- Lean-verified
- Publication
- Announced
- Significance
- 5 / 100
- Disclosed cost
- —
- Wikipedia
- No dedicated article
What the AI did
The infinite counterexample family was found with GPT-5.6 Sol Max running in Codex; verified in Lean plus independent Python and C++ enumeration.
Verification
Lean-checked disproof in the google-deepmind/formal-conjectures repository, with independent computational enumeration.