Anthropic's 1000-Agent Team Formalizes Fermat's Last Theorem

Episode 1 · Anthropic's 1000-Agent Team Formalizes Fermat's Last Theorem in 30 Hours (2026-11-11, 6 posts)

Anthropic announced that a team of roughly 1000 agents formalized the proof of Fermat's Last Theorem—converting the existing mathematical proof into Lean machine-checkable form. A second run took 30 hours, down from 11 days for the earlier run. Lance Martin of Anthropic shared the practice in a talk at the AI Engineer Code Summit.

Confirmed

• About 1000 agents completed the formalization in 30 hours; a previous run took 11 days (@svenai, @petrusenkomax).
• A shared figure shows 29,511 statements by day 11 of the project (@svenai).
• Lance Martin discussed the practice, his core views on long-horizon agents, and a second article on agent memory plus tools (@RLanceMartin, @FinanceYF5, @SimplyAnnisa).

Unconfirmed

• Posts differ on the model used: some say Claude (@FinanceYF5, @SimplyAnnisa), others Fable 5.2 (@RLanceMartin, @svenai); the official naming remains unverified.
• @randlongevity's mention of a Yang-Mills construction approved by a Nobel laureate-led committee is not corroborated by other posts.

Why it matters

• A landmark demonstration of large-scale multi-agent collaboration in formalized mathematics, showing the scalability of long-horizon agents on complex, verifiable tasks.
• As commenters under @petrusenkomax noted, machine-checkable output is the key precondition for 1000 agents to work in concert; such experience may not transfer to domains lacking verifiability.

• Anthropic's Fable 5.2 Formalizes Fermat's Last Theorem Proof in 30 Hours with ~1,000 Agents — sven_ai · 2026-11-11
• 1,000 AI agents re-proved Fermat's Last Theorem in 30 hours — but only because output is machine-checkable — petrusenko_max · 2026-11-12
• Talk preview: scaling 1,000 Fable 5.2 agents to formalize Fermat's Last Theorem — RLanceMartin · 2026-11-12
• AI formalizes Fermat's Last Theorem in 30 hours, Yang-Mills construction wins Nobel laureate committee sign-off — rand_longevity · 2026-11-12
• Anthropic's Lance Martin Scaled 1,000 Claude Agents to Formalize Fermat's Last Theorem — FinanceYF5 · 2026-11-12
• Anthropic scaled 1,000 Claude agents to formalize Fermat's Last Theorem — SimplyAnnisa · 2026-11-12

Episode 2 · 1,000 Claude Agents Team Up to Formally Prove Fermat's Last Theorem (2026-11-13, 3 posts)

Anthropic demonstrated 1,000 Claude agents collaborating over 11 days to formally prove Fermat's Last Theorem in 13 million lines of Lean. Its Thousand-Agent Harness docs show the new Fable 5.2 compressed the task to just 28.7 hours.

• 1,000 Claude agents formalize Fermat's Last Theorem in 11 days, 13M lines of Lean — FinanceYF5 · 2026-11-13
• Anthropic's Lance Martin: 1,000 Claude Agents Proved Fermat's Last Theorem in 28.7 Hours — FinanceYF5 · 2026-11-13
• Anthropic's thousand-agent harness: 11 days of work in 28.7 hours — blaizedsouza · 2026-11-14