New benchmark: formalizing Fermat's Last Theorem — Fable 5.2 hits 100%, Opus 5.5 stalls at 27%
appenz · x · 2026-11-10
appenz shared a "latest benchmark": having models formally prove Fermat's Last Theorem, quipping "what a time to be alive."
The chart shows Fable 5.2 driving the weighted completion to 1.00 within 30 hours (0.86 by hour 18, finished with a 12-hour resume), while Opus 5.5 stalled at just 0.27 after 30 hours. Using one of math's most famous proofs as a formalization benchmark makes the capability gap stark.
Related event: 1,000 Fable 5.2 Agents Fully Formalize Fermat's Last Theorem in 30 Hours(12 posts)→
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