Evidence row 72546

What was observed

{
  "endpoints": [
    [
      "x402",
      "https://combinatorics.openverbs.com/v1/combinations"
    ]
  ],
  "name": "Combinations (nCr)",
  "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": "Binomial coefficient nCr = n!/(r!(n-r)!), the number of unordered r-subsets of n. Requires r ≤ n and min(r, n-r) ≤ 10000.",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "n": "42",
              "r": "42"
            },
            "bodyType": "json",
            "method": "POST",
            "type": "http"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "body": {
                  "additionalProperties": false,
                  "properties": {
                    "n": {
                      "description": "Non-negative integer ≤ 1000000.",
                      "pattern": "^\\d+$",
                      "type": "string"
                    },
                    "r": {
                      "description": "Non-negative integer, r ≤ n.",
                      "pattern": "^\\d+$",
                      "type": "string"
                    }
                  },
                  "required": [
                    "n",
                    "r"
                  ],
                  "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": "2026-10-08T05:38:35.76Z",
    "quality": {
      "l30DaysTotalCalls": 2,
      "l30DaysUniquePayers": 2,
      "lastCalledAt": "2026-10-08T05:38:35.475Z"
    },
    "resource": "https://combinatorics.openverbs.com/v1/combinations",
    "serviceName": "Combinations (nCr)",
    "tags": [
      "combinations ncr",
      "compute combinations",
      "binomial coefficient",
      "ncr api",
      "choose r from n"
    ],
    "type": "http",
    "x402Version": 2
  },
  "source": "x402_bazaar",
  "summary": "Binomial coefficient nCr = n!/(r!(n-r)!), the number of unordered r-subsets of n. Requires r ≤ n and min(r, n-r) ≤ 10000."
}

What the leaf hashes

{"body":"c15c9acbad46e94eff8c60115d22c633df2dd33ba188d9df95568fa5f987eb23","id":72546,"kind":"listing","method":"baseline/1","observed_us":1793025486196296,"prev":null,"subject":"x402_bazaar:https://combinatorics.openverbs.com/v1/combinations","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. 0x14eb48375ac15dcfbce37f70fb4875c0417187b9cc85c05ed21e07cb2da10c2e
2. 0x48e5324851b4f6fcb80abcb54b99476afc539862864b3528d2a0b9a5a4407e27
3. 0x7c0dd291fa226c83ee4b29175af3bcbb698a56c3db5fef1a8d1be6b3aa3a459f
4. 0x5ba6d341501ede6801df0075ac66a424d0519b82b0d02c5b3047a581edf620d9
5. 0x79436c5710edbebe5bdbbf6e3aa0663624ae6b6c7f157212d37a54148a751997
6. 0x86bed902bcee077ea9d87af20727dd6f2453aa1528cd0aa5a5e4fef2b28ef1a1
7. 0xbd2613fc99e41c6b77837db84f64a02e1ce70520b62d1d7c48c68633de2a8937
8. 0xa00eef3cb2069a9874199bff4cb3a870841dfd22a67680306c731fdfc0edefc9
9. 0xef11a71beed9d9f71f58bb83457901650436413ebd22769e10ada1db356dabd0
10. 0x008cbf3247d4503d443f28c4c20ecbbf230ffd5cf8ab0fd65a43b17b5b4825ba
11. 0xb5d5212c69fb335bad2409aa4a0da0469cc6cc62939ca82d5235005f3b154a2b
12. 0x2412cb8bc4d10d94e1eb907d5058dd12133e55416609e1b314e811af76620542
13. 0xff1c28bdf595a3d1333e9915edc68e9c5fded7bd5923fa85870979af34cbc3b3
14. 0xb49e8c2564256e5322e375cb619d9ac70fd17c1d1eba9c991bba4cb6428f45cc
15. 0x60582ab4b41e72eb70eb0bce07fbf0fb4d2b62a8bad5be50f5d16d511adc746c
16. 0xc6a4d7899a0f442958e26505011190b7cff2483611c1b94eba9043e0ba9ac36e
17. 0x8c756542e482157df0c36464d75c937b845e4423dbbcfad08f0cf8d5a16b9a13
18. 0x20704208aa6923d6b2450ef74ede87a6e0265d46447926038fe9506e9e154b2d
19. 0x9b9ce5b74b9bab5121612ef6b64920a8d453cbf311096a423eef9702747e868a

Day root

0xf43e8dcc3d451a4788b26be904c55e8c4c0fa75c9666796c51db38d37e2c0df8

Chained

0x702d5ac508f08b0d1accf36af25822d8e5660367494edd17a642fb61e158a57a

Published

On Arc Testnet, block 69251483: 0x495162f8936e19f0039918feebe6c307f327cd6bf8c37219620b1970041fa9ae