Researchers built an AI agent that searches for mathematical proofs and submits them to Lean, a system that automatically checks each logical step. A more advanced version solved nine of 353 formalized open Erdős problems, including two that had been open for 56 years, and proved 44 of 492 formalized Online Encyclopedia of Integer Sequences conjectures.
The agent combined language-model-generated proof attempts with compiler feedback and, in some versions, additional proof tools and an evolutionary search over candidate arguments. The researchers report that a simpler agent using repeated generation and Lean verification also reproduced the Erdős results, although it was more costly on the hardest problems.



