Draft — mutable and not usable as a dependency; its citation marks the draft state.

Proof of `Two-way transducers are closed under composition`

groundedproofs/Lax916827Proofs/Results.lean · lax-916827

What this proof establishes

no assumptions

Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.

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In the paper

Description

Two-way transducers are closed under composition (Theorem C.2.5), Transducers.twoWaycompTransducers.twoWay_comp: the second transducer is simulated on the run of the first, walking backwards along the run when it moves left.

Attribution

Theorem C.2.5 of Transducers, Part C (Chytil and Jákl); formalised by Aristotle (Harmonic), PartC/TwoWayComp.leanPartC/TwoWayComp*.lean.