Formalizing Fermat's Last Theorem

Claude, an AI system developed by Anthropic, has completed the first fully computer-checked proof of Fermat's Last Theorem in just 11 days, writing 13 million lines of code in the Lean programming language and proving 29,500 intermediate theorems. This achievement represents a major breakthrough in automated formalization—the conversion of complex mathematical proofs into computer-verifiable form—which could significantly accelerate the verification of future mathematical results. The work demonstrates that AI-generated proofs are now robust enough to build upon and could help reduce the years typically required to verify and trust new mathematical discoveries.