Formal-proof fidelity audit

The Erdős frontier, read from the proofs

Which “formally solved” Erdős problems rest on an unconditional Lean proof, and which silently assume an unproven result.

A proof can be sorry-free and #print axioms-clean and still prove the problem only conditionally, by taking a deep theorem as a hypothesis parameter the axiom check never sees. How the audit works, and what it cannot do →

    Axis 1 · the proof

    Is the proof unconditional?

    Read mechanically from each hosted Lean proof: the axioms it uses and the Prop hypotheses it takes as parameters. A fact, not a judgment.

    machine · deterministic

    Axis 2 · the statement

    Is that the right problem?

    Whether the formal statement faithfully states the boxed problem. A passing proof checks the statement, not that the statement is the problem.

    signed · named reviewer
    #ProofConditional on StatementExternal claim