{
  "schema_version": "1.0.0",
  "source": "vibemath",
  "problem_id": "vibemathed:unrestricted-multiplicative-complexity-mul4",
  "title": "Unrestricted Boolean multiplicative complexity of four-term binary polynomial multiplication",
  "canonical_statement": "Let Mul4: F_2^8 -> F_2^7 output the seven coefficients of the product of two four-term binary polynomials. The manuscript proves that its unrestricted XOR--AND multiplicative complexity is exactly 9. The upper bound is a nine-AND Karatsuba--Ofman construction. The lower bound rules out every unrestricted eight-AND circuit, including circuits that reuse nonlinear intermediate wires and exploit Boolean idempotence. Thus, for this natural vector-valued quadratic function, allowing nonlinear feedback does not improve on the optimal quadratic circuit.",
  "plain_summary": "VibeMathed reports this item as partial. VibeMath preserves that report as a source assertion and has not independently authored a plain-language mathematical explanation.",
  "current_status": "partial",
  "solution_events": [
    {
      "id": "vibemathed:unrestricted-multiplicative-complexity-mul4:event",
      "problem_id": "vibemathed:unrestricted-multiplicative-complexity-mul4",
      "type": "proved",
      "status": "partial",
      "occurred_at": "2026-08-31T00:00:00.000Z",
      "title": "arXiv",
      "summary": "The exact Mul4 instance is resolved: its unrestricted XOR--AND multiplicative complexity is 9. The restricted bilinear/quadratic value 9 was classical; the new theorem proves that arbitrary nonlinear Boolean reuse cannot lower it. This is a natural positive special case of the Boyar--Find question, not a solution of the general (n,m) problem. The lower bound is a conceptual structural argument. A complete Lean 4 formalization checks the unrestricted circuit semantics and the exact equality, while the development-time Python/C++ programs remain independent regression checks rather than logical premises. The corresponding unrestricted questions for five or more terms remain open. Independent statement-fidelity review remains pending.",
      "ai_contribution": "ai_assisted",
      "attempt_ids": [
        "vibemathed:unrestricted-multiplicative-complexity-mul4:attempt"
      ],
      "method_family_ids": [
        "vibemathed:unrestricted-multiplicative-complexity-mul4:method"
      ],
      "source_assertion_ids": [
        "vibemathed:unrestricted-multiplicative-complexity-mul4:assertion"
      ]
    }
  ],
  "attempts": [
    {
      "id": "vibemathed:unrestricted-multiplicative-complexity-mul4:attempt",
      "problem_id": "vibemathed:unrestricted-multiplicative-complexity-mul4",
      "model": "OpenAI GPT-5.6 Sol (extra-high); Anthropic Opus 5 (high, referee)",
      "provider": "OpenAI; Anthropic",
      "attempted_at": "2026-08-31T00:00:00.000Z",
      "human_collaborators": [],
      "exposure": "unknown",
      "prompt_public": null,
      "outcome": "OpenAI GPT-5.6 Sol in extra-high thinking mode was used for research, proof exploration and development, computational checking, Lean 4 formalization and formal-proof engineering, literature and citation verification, manuscript drafting and revision, and release and submission preparation. Anthropic Opus 5 in high thinking mode was used as a critical referee, not as the discovery model. The public disclosure does not attribute a named essential lemma or the central informal proof solely to a model, so the conservative AI-assisted tier is retained rather than AI co-developed or AI-discovered. Gregory Morse directed and reviewed the mathematical claims, informal and formal proofs, computations, citations, code, and manuscript text and assumes full responsibility.",
      "failed_routes": [],
      "artifacts": [
        {
          "label": "Boyar--Find finite-field question",
          "url": "https://arxiv.org/abs/1407.6169v1",
          "kind": "problem-record",
          "license": null
        },
        {
          "label": "Complete Lean proof and immutable verification release",
          "url": "https://github.com/GregoryMorse/unrestricted-boolean-mul/releases/tag/n4-arxiv-v2",
          "kind": "lean-proof",
          "license": null
        },
        {
          "label": "Headline theorem MC(Mul 4) = 9",
          "url": "https://github.com/GregoryMorse/unrestricted-boolean-mul/blob/n4-arxiv-v2/UnrestrictedBooleanMul/N4/Main.lean",
          "kind": "lean-statement",
          "license": null
        },
        {
          "label": "Rebuilt here: lake build, axiom audit and leanchecker replay",
          "url": "https://github.com/mrconter1/vibemathed/actions/runs/33722071409",
          "kind": "independent",
          "license": null
        }
      ],
      "sources": [
        {
          "label": "arXiv",
          "url": "https://arxiv.org/abs/2608.30238",
          "kind": "primary-mathematical-source",
          "license": null
        },
        {
          "label": "VibeMathed: Unrestricted Boolean multiplicative complexity of four-term binary polynomial multiplication",
          "url": "https://vibemathed.com/problem/unrestricted-multiplicative-complexity-mul4",
          "kind": "source-assertion",
          "license": "https://vibemathed.com/data-license"
        }
      ],
      "cost_usd": null,
      "independence": "unknown"
    }
  ],
  "verifications": [
    {
      "id": "vibemathed:unrestricted-multiplicative-complexity-mul4:verification",
      "problem_id": "vibemathed:unrestricted-multiplicative-complexity-mul4",
      "solution_event_id": "vibemathed:unrestricted-multiplicative-complexity-mul4:event",
      "level": "unreviewed",
      "mathematical_correctness": "unknown",
      "statement_fidelity": "unaudited",
      "peer_review": "none",
      "verifier": "VibeMathed (source-reported label)",
      "verified_at": null,
      "note": "Site-confirmed: rebuilt here on 3 September 2026, not taken from the author's CI badge. This site's verify-lean workflow checked out release n4-arxiv-v2 (commit 2ebc0cf4) of GregoryMorse/unrestricted-boolean-mul, installed the toolchain the repository pins (leanprover/lean4:v4.32.1), ran $\\texttt{lake build}$ over every module, then the project's own AxiomAudit.lean, then $\\texttt{lake env leanchecker}$ replaying the whole UnrestrictedBooleanMul environment. 24m40s, every step green.\n\nAll six headline theorems - the exact values for $n = 0,1,2,3$, the eight-gate impossibility and $\\mathrm{MC}(\\mathrm{Mul}\\,4) = 9$ - report $\\texttt{propext}$, $\\texttt{Classical.choice}$ and $\\texttt{Quot.sound}$ and nothing else. No $\\texttt{sorryAx}$, no project axiom, no $\\texttt{native\\_decide}$, no $\\texttt{bv\\_decide}$.\n\nThe release tag is one commit ahead of 1533276b, which the author's own run used; that commit touches only READMEs, a citation file and checksum lists, no Lean source.\n\nNot Lean-verified. The kernel checks the proof against the statement the author wrote; whether that statement expresses the Boyar-Find question is the anchoring half, and nobody without a stake has audited it.",
      "sources": [
        {
          "label": "VibeMathed: Unrestricted Boolean multiplicative complexity of four-term binary polynomial multiplication",
          "url": "https://vibemathed.com/problem/unrestricted-multiplicative-complexity-mul4",
          "kind": "source-assertion",
          "license": "https://vibemathed.com/data-license"
        },
        {
          "label": "arXiv",
          "url": "https://arxiv.org/abs/2608.30238",
          "kind": "primary-mathematical-source",
          "license": null
        }
      ]
    }
  ],
  "sources": [
    {
      "label": "arXiv",
      "url": "https://arxiv.org/abs/2608.30238",
      "kind": "primary-mathematical-source",
      "license": null
    },
    {
      "label": "VibeMathed: Unrestricted Boolean multiplicative complexity of four-term binary polynomial multiplication",
      "url": "https://vibemathed.com/problem/unrestricted-multiplicative-complexity-mul4",
      "kind": "source-assertion",
      "license": "https://vibemathed.com/data-license"
    }
  ],
  "recommended_mode": "expand",
  "recommended_exposure": "result_only",
  "opportunity_signals": [
    {
      "id": "vibemathed:unrestricted-multiplicative-complexity-mul4:signal:recent_partial_result",
      "problem_id": "vibemathed:unrestricted-multiplicative-complexity-mul4",
      "kind": "recent_partial_result",
      "reason": "A source-reported partial result may support bounded expansion.",
      "generated_at": "2026-09-13T16:28:40.178Z"
    }
  ],
  "uncertainties": [
    "VibeMath has not independently verified the mathematical claim.",
    "AI-attempt independence and training-data exposure are unknown unless explicitly documented.",
    "VibeMath has not independently audited the mathematical statement, proof, or novelty claim."
  ],
  "generated_at": "2026-09-13T16:28:40.178Z"
}
