{
 "schema_version": "0.2",
 "name": "[[64,14,4]] 2D-local weight-8 SAT code on an 8x8 grid",
 "code_type": "CSS",
 "n": 64,
 "k": 14,
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 "distance": {
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  "X": {
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   "confidence": "upper_bound",
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  "Z": {
   "value": 4,
   "confidence": "upper_bound",
   "witness": [
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 },
 "provenance": {
  "authors": [
   "@vprusso"
  ],
  "origin": "submission",
  "model": "Claude Fable 5.1 (Claude Code)",
  "construction": "SAT search (research/local_sat.py build_local_cnf, n_side=8, G=25, max_weight=8, t=3 detection, anchor radius 2.0, shared_t3 encoding, lazy exact detection, CaDiCaL 1.9.5 via python-sat) over 2D-local CSS codes on an 8x8 grid; each check is anchored at a grid site and acts within radius 2.0 of it, so the interaction radius is at most 4.0 by construction. Model index 0 of the enumeration; distance is a witness-backed upper bound.",
  "references": [],
  "date": "2026-10-04",
  "notes": ""
 },
 "family": "local-sat-css",
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  "layers": 1
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 "circuit": {
  "d_circ": {
   "Z": {
    "value": 2,
    "confidence": "upper_bound",
    "witness": [
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   },
   "X": {
    "value": 2,
    "confidence": "upper_bound",
    "witness": [
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  },
  "rounds": 4,
  "stim_version": "1.16.0",
  "notes": "Generic sequential two-block extraction: one ancilla per check, X checks then Z checks each round with joint reset and measurement layers; CX layers are a proper edge coloring of each Tanner graph (8 X + 8 Z CX layers per round, coloring candidate 0); generated by qldpc submit (research/circuit_autogen.py, seed 0), the first of up to 6 candidates whose RIS screen at 2 rounds found nothing below d; witnesses from RIS on ker(H_dem) at twice the gate's trial budget, validated in GF(2)",
  "contributed_by": {
   "by": [
    "@vprusso"
   ],
   "date": "2026-10-05",
   "method": "circuit_autogen schedule search (two-block interleaved, then layout, then generic), verified by verify/circuit_verify.py before writing"
  }
 }
}