Evidence row 116734

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://matrix.openverbs.com/v1/solve"
    ]
  ],
  "name": "Solve a linear system",
  "owner_address": "0xb3f4de103f34b99f0da19b4f16d6b53a14c2194a",
  "raw": {
    "accepts": [
      {
        "amount": "4000",
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2"
        },
        "maxTimeoutSeconds": 300,
        "network": "eip155:8453",
        "payTo": "0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A",
        "scheme": "exact"
      }
    ],
    "description": "Solve the linear system A·x = b for a square coefficient matrix A and vector b via Gaussian elimination with partial pivoting. A non-square A or a b of the wrong length is a clean 400. A singular system is NOT an error — it returns a successful { solvable:false, solution:null }.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "a": [
                [
                  1
                ]
              ],
              "b": [
                1
              ]
            },
            "bodyType": "json",
            "method": "POST",
            "type": "http"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "body": {
                  "additionalProperties": false,
                  "properties": {
                    "a": {
                      "description": "Square coefficient matrix (n×n).",
                      "items": {
                        "items": {
                          "type": "number"
                        },
                        "minItems": 1,
                        "type": "array"
                      },
                      "minItems": 1,
                      "type": "array"
                    },
                    "b": {
                      "description": "Right-hand-side vector (length n).",
                      "items": {
                        "type": "number"
                      },
                      "minItems": 1,
                      "type": "array"
                    }
                  },
                  "required": [
                    "a",
                    "b"
                  ],
                  "type": "object"
                },
                "bodyType": {
                  "enum": [
                    "json",
                    "form-data",
                    "text"
                  ],
                  "type": "string"
                },
                "method": {
                  "enum": [
                    "POST"
                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    },
    "lastUpdated": "2026-10-02T13:33:27.483Z",
    "quality": {
      "l30DaysTotalCalls": 2,
      "l30DaysUniquePayers": 2,
      "lastCalledAt": "2026-10-02T13:33:27.218Z"
    },
    "resource": "https://matrix.openverbs.com/v1/solve",
    "serviceName": "Solve a linear system",
    "tags": [
      "solve linear system",
      "linear equation solver",
      "matrix solve ax b",
      "gaussian elimination solver",
      "solve coefficients vector"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Solve the linear system A·x = b for a square coefficient matrix A and vector b via Gaussian elimination with partial pivoting. A non-square A or a b of the wrong length is a clean 400. A singular system is NOT an error — it returns a successful { solvable:false, solution:null }."
}

What the leaf hashes

{"body":"c831bd8a0c91115cf22ae66a481ca7d3bd2d9546819f0b9dc00752c1c93b7bbb","id":116734,"kind":"listing","method":"baseline/1","observed_us":1793025610218991,"prev":null,"subject":"x402_bazaar:https://matrix.openverbs.com/v1/solve","subject_kind":"source_record"}

Proof

Fold these into the leaf in order, hashing each sorted pair with keccak256, to reach the root of 2026-10-26 (296695 rows).

1. 0x7d201cd0ebbbe2ef2bfda4a072745d68659b6494467b7915867ed1ecc47e458c
2. 0xdc9abb59e396f98a2989b4c56cff186908fa2ab961a236d47c79db1df5ed554c
3. 0x7560097723308aa3742b43cb29eb650e98d1caeef9e44795522c6c38862ea689
4. 0x7b954c7659b61786e0be99c3ed2485e0a637af7ebec3596678a28fc1c54fbc75
5. 0x4cb3abc7c97c2d8e0e3477eb371792cad45b0d28ef3fac0beac4eae27a7e42fa
6. 0xd292a9f6562eef28b44581c7ba9b135902527f9cd1083cd5c73597ed653d60b6
7. 0xb7392e24404c3e722f0d32536c363562e0da4429dfe6ec0dc805b8261db68a0a
8. 0xb6ad5ba14232f23ff30fb6b9fe383205836e99b8885d9cedab333b250ef72972
9. 0x7e1ec73780098fac490af117915a41a976dff267e71b952d3a320caa7180a1e1
10. 0x27bb9eefd00206cde7209859f541e1ae68cb3baba4968278bfa6a4028b0fe719
11. 0x05b818019343d04f2973b36329a447f88301721891653961b94822610edda553
12. 0x779c77295186b32da6387dfb36d3a76522e7d713472a7cebed7c93529ccc4be6
13. 0x0bffb634300aa5609bddaa79e8d31d7cde36c0a5a4465472f809b9f5287e40d2
14. 0x7721d38652b6444b18e1193824e50490ade04851ce6221771f6e374c4527d80f
15. 0x15039087bf60ae9b06b756ec3cbc299760e59923a438bbd91e34d105186db0ed
16. 0x2b6e23e3624a1b66e1d2298cfbce99a93ce6b13d24a58112a71802d79c5f7a76
17. 0xd21942ae3214eff88e08ab04884fd4b11958b51af9a0741b7668e2d07a2c56c9
18. 0x9a9024edb5069d88a324facb310a5ce8e495214bbaa968f077bede437390194f
19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a

Day root

0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8

Chained

0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a

Published

On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae