Mathlib theorem · Existing formal mathematics

Lean verification record

Checked Artifact: Myhill–Nerode Theorem (mathlib)

Proof Atlas collected build, no-sorry, axiom, and clean-source evidence directly from the pinned upstream declaration.

Verification result

The recorded Lean checks passed

  • Build replaypassed with retained transcript
  • Unfinished stepsNone found
  • Source identityPinned commit and file recorded
  • Dependency profileAxiom closure recorded

Reproducibility details

What the checker recorded

Declaration checked
Language.isRegular_iff_finite_range_leftQuotient
Module
Mathlib.Computability.MyhillNerode
Source file checked
Mathlib/Computability/MyhillNerode.lean
Package commit
5e932f97dd25535344f80f9dd8da3aab83df0fe6
Build transcript
passed · retained with this record
Unfinished proof steps
None found by the recorded no-sorry scan
Axiom closure
Classical.choice, Quot.sound, propext
Collection provenance
Clean source state recorded

ProofAtlas record

What has been checked

Upstream indexedPinned source bytes verified locally
Locally reproducedExact upstream declaration replayed
Reviewed pageCurrent public presentation reviewed
Accepted Atlas resultNot recorded for the preferred artifact

Mathlib is the source of the theorem; the local Lean replay and page review are separate.

Evidence boundary

Exact formal statement only

This target indexes Mathlib's left-quotient formulation of the Myhill–Nerode theorem. For a language L, leftQuotient sends a word x to the language of suffixes y such that x ++ y ∈ L. The theorem identifies regularity of L with finiteness of the range of that function. It does not, in this declaration, assert uniqueness of a minimal DFA, state finite index of the Nerode equivalence, or derive the pumping lemma.

This checker record does not establish novelty, transfer a historical acceptance decision, or authorize publication.