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 "provenance": {
  "authors": [
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  "construction": "Reconstructed from qecdb.org record (see provenance.references); H-field X/Z row split, k recomputed, witnesses from the kit's random search.",
  "origin": "submission",
  "date": "2026-08-15",
  "model": "DeepSeek V4 Flash 0731",
  "notes": " LAYOUT added 2026-08-20: a 1-layer planar layout with measured interaction radius 6.0828 (integer-grid sites, min site spacing 1.0, at most 1 qubits per site), placing the code in the local-2d-bilayer class with geometric efficiency g = 0.0093. Layout credit and method are recorded in locality.contributed_by; the code, its distance claims, and its authorship are unchanged. Part of the layout-filling effort (issue #654 discussion)."
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