Tightest way to pack 11 squares proven and computer-checked

The 11SquaresFormalized project says it has proven the tightest way to pack 11 squares, and a computer has double-checked the work. All 7,920 local Lean check files, like individual answer sheets, were approved with no skipped steps in the final audit, using built-in math receipts, according to the repository published Oct. 7, 2026.