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 "name": "[[70,6,9]] bivariate bicycle code, Walking Cat Q70 (arXiv:2604.19481)",
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 "k": 6,
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   "confidence": "upper_bound",
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 "provenance": {
  "authors": [
   "Tripier, Felix",
   "Chung, Woo Chang",
   "Young, Jacob",
   "Alam, Safwan",
   "Bjork, Bryce",
   "Brodutch, Aharon",
   "Buessen, Finn Lasse",
   "Coble, Nolan J.",
   "Dellaert, Thomas",
   "Maslov, Dmitri",
   "Roetteler, Martin",
   "Tham, Edwin",
   "Webster, Mark",
   "Ye, Min",
   "Gamble, John",
   "Maksymov, Andrii",
   "Marceaux, J. P.",
   "Delfosse, Nicolas"
  ],
  "origin": "baseline",
  "construction": "Bivariate bicycle code with l = 7, m = 5, x = S_7 (x) I_5, y = I_7 (x) S_5 (S the cyclic shift matrix), A = y^2 + x^2 + x^3 + x^4, B = y + x + x^3, H_X = [A | B], H_Z = [B^T | A^T]; code Q70 of Table XXX of arXiv:2604.19481 (Tripier et al., the Walking Cat architecture). Rebuilt here from those polynomials; n, k, and the check weight 7 reproduce the paper's values.",
  "date": "2026-04-21",
  "references": [
   "arXiv:2604.19481"
  ],
  "notes": "Literature baseline: a reproduction of code Q70 of arXiv:2604.19481 (Table XXX), not a new construction and not a new parameter set. Same parameters as 70-6-9, which reproduces a row of Lin and Pryadko's 2BGA database (July 2023), but a different code: each side of both codes has exactly 35 minimum-weight stabilizers, and nauty finds no isomorphism between the typed Tanner graphs on those complete sets, with or without an X/Z swap, so a signature match against 70-6-9 is two inequivalent codes with the same parameters. The paper reports d = 9; this entry carries witness-backed upper bounds from the board's own search until certified. Seeded after Nicolas Delfosse (IonQ) reported the code in review of the QEC Challenge paper.",
  "novelty": "known_parameters",
  "model": "Claude Fable 5.1 (Claude Code)"
 },
 "family": "bivariate-bicycle"
}