Observed arrival · 2026-10-17
MachineChecked puts paper claims beside Lean proofs
A local reader for mathematical papers and their Lean formalisations, with tools to connect statements and inspect proof status.
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- For
- Mathematics authors and Lean users reviewing formalised papers
- Worth noticing
- It separates mechanically checked Lean statements from the human judgment that they correspond to the paper.
Field notes
The synthetic demo uses Proposition 2.3 to show how a paper claim can fail in Lean: it says every natural number is greater than its predecessor, but 0 − 1 = 0. The page marks that printed statement refuted and gives a corrected version, restricted to n ≥ 1, as proved. The setup runs inside a Lean project and lists Python 3.11+ as a requirement, with TeX Live needed for LaTeX papers.
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