Evidence row 2202260

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://audio-calc.x402tookit.com/interval-ratio"
    ]
  ],
  "name": "Audio Calc",
  "owner_address": "0xb531320805c5bed1d46aeadcf4f008fdf172dbda",
  "raw": {
    "accepts": [
      {
        "amount": "20000",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 300,
        "network": "eip155:8453",
        "payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
        "scheme": "exact"
      },
      {
        "amount": "20000",
        "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
        "extra": {
          "feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM",
          "transactionVersions": [
            0
          ]
        },
        "maxTimeoutSeconds": 300,
        "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
        "payTo": "DUPiupXtuox38dcGoXUKer5mAydCzmaHjrbQ66qeEm8s",
        "scheme": "exact"
      },
      {
        "amount": "20000",
        "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 300,
        "network": "eip155:137",
        "payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
        "scheme": "exact"
      },
      {
        "amount": "20000",
        "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 300,
        "network": "eip155:42161",
        "payTo": "0xb531320805C5BED1D46AEaDcF4F008FDF172DBDa",
        "scheme": "exact"
      }
    ],
    "description": "Convert a frequency ratio (3:2) to cents and semitones or back, name just and Pythagorean intervals and commas, apply to Hz.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "method": "GET",
            "queryParams": {
              "baseHz": 440,
              "ratio": "3:2"
            },
            "type": "http"
          },
          "output": {
            "example": {
              "asOf": "2026-10-11T14:38:34.612Z",
              "baseHz": 440,
              "cents": 701.955001,
              "centsFromEqualTemperament": 1.955001,
              "degraded": false,
              "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
              "intervalName": "perfect fifth",
              "nearestNamedCentsAway": 0,
              "nearestNamedInterval": "perfect fifth",
              "nearestNamedRatio": "3:2",
              "nearestSemitones": 7,
              "notChecked": [
                "which note names an interval takes in a given tuning (see /tuning-temperament)",
                "how pitch is perceived: tiny commas are audible only as beating or drift",
                "…1 more"
              ],
              "octaveReducedCents": 701.955001,
              "octaves": 0.5849625,
              "ratio": 1.5,
              "reasons": [
                "Cents are logarithmic: 100 per equal-tempered semitone, 1200 per octave.",
                "Recognised as perfect fifth."
              ],
              "resultHz": 660,
              "semitones": 7.01955,
              "simpleFraction": "3:2",
              "source": "cents = 1200 log2(ratio); just, Pythagorean and septimal interval ratios, computed locally",
              "summary": "Ratio 1.5 = 701.955 cents = 7.0196 semitones (perfect fifth); nearest equal-tempered interval is 7 semitones (+1.96 cents).",
              "verdict": "NAMED_INTERVAL"
            },
            "type": "json"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "method": {
                  "enum": [
                    "GET"
                  ],
                  "type": "string"
                },
                "queryParams": {
                  "properties": {
                    "baseHz": {
                      "description": "Optional starting frequency in Hz to apply the interval to",
                      "type": "number"
                    },
                    "cents": {
                      "description": "Interval size in cents (1200 per octave)",
                      "type": "number"
                    },
                    "ratio": {
                      "description": "Frequency ratio such as 3:2, 5/4 or 1.5 (use this, or cents)",
                      "type": "string"
                    }
                  },
                  "required": [],
                  "type": "object"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method"
              ],
              "type": "object"
            },
            "output": {
              "properties": {
                "example": {
                  "properties": {
                    "asOf": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "baseHz": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "cents": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "centsFromEqualTemperament": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "degraded": {
                      "type": [
                        "boolean",
                        "null"
                      ]
                    },
                    "disclaimer": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "intervalName": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "nearestNamedCentsAway": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "nearestNamedInterval": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "nearestNamedRatio": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "nearestSemitones": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "notChecked": {
                      "items": {
                        "type": "string"
                      },
                      "type": [
                        "array",
                        "null"
                      ]
                    },
                    "octaveReducedCents": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "octaves": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "ratio": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "reasons": {
                      "items": {
                        "type": "string"
                      },
                      "type": [
                        "array",
                        "null"
                      ]
                    },
                    "resultHz": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "semitones": {
                      "type": [
                        "null",
                        "number"
                      ]
                    },
                    "simpleFraction": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "source": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "summary": {
                      "type": [
                        "null",
                        "string"
                      ]
                    },
                    "verdict": {
                      "type": [
                        "null",
                        "string"
                      ]
                    }
                  },
                  "type": "object"
                },
                "type": {
                  "type": "string"
                }
              },
              "required": [
                "type"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-11-01T22:36:39.388Z",
    "quality": {
      "l30DaysTotalCalls": 2,
      "l30DaysUniquePayers": 2,
      "lastCalledAt": "2026-11-01T22:36:39.227Z"
    },
    "resource": "https://audio-calc.x402tookit.com/interval-ratio",
    "serviceName": "Audio Calc",
    "tags": [
      "audio",
      "cents",
      "just-intonation",
      "ratio"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Convert a frequency ratio (3:2) to cents and semitones or back, name just and Pythagorean intervals and commas, apply to Hz."
}

What the leaf hashes

{"body":"398a49697c5ed7c36ef072774a0334483aa2831a9877c2186f83c2bb92a68227","id":2202260,"kind":"listing","method":"sync.x402_bazaar/1","observed_us":1793646814771488,"prev":null,"subject":"x402_bazaar:https://audio-calc.x402tookit.com/interval-ratio","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-11-02 (444186 rows).

1. 0xbcf9cf2eab814b15ae9fccedae410643a7d1f8f6652765399c062b5f8c878dc3
2. 0xc34d497dc571f29a40378be73d5a133c2e4e62a4f26736623ad4f5608e9eb2b5
3. 0x9aba9381b49d5b2dfc40c2378d9217f650a290d3d41e3b6285bc30b612a79ba5
4. 0x3b9cf7e2c616475c21e5e73dbad4fa3381583dc08d9ba224011fca3e28cc17a1
5. 0x161fead11360c29b72a1e8adc6894c5594309ec76f4f6092751bfe4d63bbea63
6. 0xeacb8d12cf79bc57415fd0c019fa01ce8d537c1af00c4f1be7432972a22ec808
7. 0x19a7cf905248985c20dc7b99fa6e1cdf918a5571b5e46aaa7ff7fd051dc6ab54
8. 0xb88167a02885cd6c94ed26e303275ec8b66819acf6399285c18b4c1cc07b589b
9. 0x77c4d3c95246b24e9ee805610529e0e5d8fdb3e270012aa01e615707f38535d7
10. 0xccb52868a012d9dfa905c6839ce59ab036519b2706cfeb0115c568e77a648fe6
11. 0x1847102c73a4da4a0ae5d43798ea14b304d15726bf8fab7c3e3440ec8e786566
12. 0x2125e33545378f38f6b289948fbb39dbb1e50e75daaac839754e4c6b0b27f9b8
13. 0x047210a388d428d19c536816e7de36503493563ebf77985dcdc7335f49f50a17
14. 0x5483702efe692d367a569024f6ed01075bb22b39176302aa223f423906e01c1e
15. 0xcbfaf790331071a9b3499a4db6f9d951fe5d04baefda2c66846b52b023ab8ae5
16. 0x37d31d28d0bd3743650d57e9fbf999efa4592cac831267f83aa125335b35a16b
17. 0xdb8bd933619a267f9790faac9839143d202be46af284371cc369cdf683f897ba
18. 0x98cbbf2c68ab4c0b4db782aeb88bea1f30b02178cf8b5d3d24a931d19492ea6d
19. 0x252cce55f1a3d5391c16f82d7f62494429a5f69b03486d4cfcfb7b2c96d6c884

Day root

0x78fecaabbe319e56f5c4b80fc02e2052e198ad24781da8832a475ff65f2002d1

Chained

0xdc35957db5d1371ca382b9152878ffece28ec7c5cb4f98fd71ddb367f8b999b2

Published

On Arc Testnet, block 70432815: 0x56b814612eb2e3e544153df3e91e1f7199106d1e430c7d8c6b653feeb9ebe9af