Math & science · September 2026

Fermat's Last Theorem machine-checked

AI agents write a complete Lean proof of Fermat's Last Theorem in 11 days.

Claude agents produced the first end-to-end Lean formalization of Fermat's Last Theorem in 11 days: 13 million lines and 29,500 lemmas, building on Kevin Buzzard's FLT project and Mathlib. Machine-checked proof of deep modern mathematics became practical.

See it in the living tree Wikipedia Source

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 2

Claude Opus 5 2026
Predicate logic 1879

Related measurements

The dashed line marks when it first worked.

Best AI score on GPQA Diamond Latest: 95.8 % correct (2026) Source: Epoch AI, Capabilities & benchmarking (benchmark_data.zip, gpqa_diamond.csv); Anthropic: Claude 3 public launch (March 4, 2024)

Training compute of notable AI models Source: Epoch AI, Notable AI Models (CC BY 4.0)