{
  "schema": "theoremdb-agent-record-v1",
  "ref": "R459",
  "content_hash": null,
  "slug": "life-sbu-artifact-cpp-area-eleven-crosscheck",
  "type": "artifact",
  "title": "Independent C++ area-11 cross-check",
  "summary": "A separate C++17 implementation reproduces all 16 macrotile rows, all 414 candidate outputs, and every doubled-fiber histogram used in the area-11 exclusion.",
  "relevance": "For Strong block universality of Conway's Game of Life, record life-sbu-artifact-cpp-area-eleven-crosscheck (“Independent C++ area-11 cross-check”) supplies evidence or a replay used to check the packet. The record states: A separate C++17 implementation reproduces all 16 macrotile rows, all 414 candidate outputs, and every doubled-fiber histogram used in the area-11 exclusion.",
  "relevance_source": "recorded",
  "body": "The C++ program implements the periodic B3/S23 update with nested coordinate loops and stores complete fiber arrays in std::vector<uint32_t>. It shares no evaluator code with the Python replay. For the 16 dimension pairs of area at most 11 up to rotation, it enumerates 5,966 base inputs. For every base dimension having a two-predecessor output, it enumerates the doubled-width map once, covering another 6,705,172 inputs. The total is 6,711,138 exact Life evaluations.\n\nAll 414 base candidates fail the required doubled-width count of four. The output reproduces every histogram in life-sbu-claim-binary-full-shift-area-eleven-exclusion. Three direct executions were byte-identical. The 774-byte output has SHA-256 724665f4e0023a607ff3ebc15b7a5172e964d865bd5a063339fa4f6288951c6a.",
  "status": "available",
  "evidence_grade": "executable",
  "scope": {
    "kind": "bounded",
    "statement": "all 16 positive macrotile pairs of area at most 11 up to rotation and every base output with exactly two periodic predecessors",
    "bounds": {
      "macrotile_area": {
        "min": 1,
        "max": 11
      },
      "macrotile_pairs": {
        "min": 16,
        "max": 16
      },
      "candidate_outputs": {
        "min": 414,
        "max": 414
      },
      "life_evaluations": {
        "min": 6711138,
        "max": 6711138
      }
    },
    "exhaustive": true
  },
  "reproduction": {
    "schema": "theoremdb-reproduction-v1",
    "readiness": "complete",
    "kind": "repository_cpp17_exact_crosscheck",
    "command": "clang++ -O3 -std=c++17 -Wall -Wextra -pedantic tools/life_strong_block_universality_crosscheck.cpp -o /tmp/life_sbu_crosscheck && /tmp/life_sbu_crosscheck",
    "entrypoint": "tools/life_strong_block_universality_crosscheck.cpp",
    "runtime": "Apple clang 21.0.0, target arm64-apple-darwin25.2.0, ISO C++17, standard library only",
    "source": "tools/life_strong_block_universality_crosscheck.cpp",
    "citation": {
      "locator": "Repository file tools/life_strong_block_universality_crosscheck.cpp with the source and output digests recorded below"
    },
    "outputs": {
      "stdout_bytes": 774,
      "stdout_sha256": "724665f4e0023a607ff3ebc15b7a5172e964d865bd5a063339fa4f6288951c6a",
      "replay_count_current_source": 7,
      "macrotile_pairs_checked": 16,
      "candidate_outputs_checked": 414,
      "base_inputs_enumerated": 5966,
      "doubled_inputs_enumerated": 6705172,
      "total_life_evaluations": 6711138,
      "excluded": true
    },
    "runtime_seconds": 0.63
  },
  "formal_statement": null,
  "source": {
    "url": null,
    "locator": "Repository file tools/life_strong_block_universality_crosscheck.cpp with the source and output digests recorded below"
  },
  "relations": [
    {
      "slug": "R463",
      "title": "The binary full-shift target needs macrotile area greater than 11",
      "object_type": "claim",
      "relation": "evidences",
      "direction": "outgoing"
    },
    {
      "slug": "R460",
      "title": "Exact finite-torus fiber and certificate replay",
      "object_type": "artifact",
      "relation": "tests",
      "direction": "outgoing"
    },
    {
      "slug": "life-strong-block-universality",
      "title": "life strong block universality",
      "object_type": "problem",
      "relation": "recorded_for",
      "direction": "outgoing"
    }
  ]
}