What was already known
The decision problem for this superintuitionistic logic was longstanding; computability of related systems does not answer it.
What changed and why it matters
Advances the stated target relative to the recorded baseline.
The AI contribution
The paper credits ChatGPT Sol 5.6 with the core idea and technical work, Claude Opus 5 with Lean verification, and the authors with methodology and mathematical communication.
Limitations
Preprint. Undecidability concerns the specified logic, not every formal system. Skvortsov logic and separation results are additional scoped claims. AIProofWatch has not rebuilt the reported formalization.
Verification evidence
Evidence labels show what supports the claim. Importance rates its impact if correct.
Author claim
The original source reports this scoped result; AIProofWatch reviewed its statement, not the full proof.
Accessible artifact / proof
A research manuscript or proof artifact is publicly accessible; availability is not independent checking.
Correction and publication history
Full source review, 11 October 2026. Historical addition; subscriber alerts disabled.
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