Internal Codex version found the same counterexample in a proof attempt
aaron_lou · x · 2026-07-21
A thread sharing a writeup from an internal version of Codex says the model found essentially the same counterexample that Levent discovered, even without web search.
The post frames this as a useful internal proof attempt: the model produced a clean summary of the strategy, and the author highlights the result as a noteworthy capability signal for Codex-style systems.
More from Models
- User catches model failing to parse 400-paper file, citing stale news sources instead — jungofthewon · 2026-10-27
- Odd eval result: Gemini 4.1 Flash gets more accurate when asked to control its CoT — dfrsrchtwts · 2026-10-27
- Poster surprised that v4.1 flash gets more accurate when asked to control its CoT — dfrsrchtwts · 2026-10-27
- Dev claims Anthropic is baking 'sabotage' into model behavior for 'wrong' engineering — cephaloform · 2026-10-27
- Gemini fails at listing unread emails, tells user to search Gmail manually — gethackteam · 2026-10-27
- Meta's Muse Spark Open goes live on Applied Compute for async RL post-training — ypatil125 · 2026-10-27