Api Endpoint

combinatorics.openverbs.com

Number of ordered arrangements of r items from n, nPr = n!/(n-r)!. Requires r ≤ n and r ≤ 10000.

Open interactive test console

Offering

Provider: combinatorics.openverbs.com
Method: GET
Offering type: Api Endpoint
Transport type: http
Category: Science And Education
Delivery: Not provided
Pricing model: Not provided
x402 version: 1

Endpoint context

URL: https://combinatorics.openverbs.com/v1/permutations
MIME type: Not provided
First seen: 2026-10-16T02:36:17.976Z
Last seen: 2026-10-26T00:14:48.818Z
Tags: None supplied

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1: 0.004 USDC
Atomic price: 4000 · Network: eip155:8453 · Asset: USDC · Scheme: exact

Raw x402 terms

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "4000",
    "payTo": "0xb3f4de103F34b99f0Da19B4F16D6B53a14C2194A"
  }
]

Observed health

Status: Healthy
Latest latency: 169 ms
Average latency: 1166 ms
HTTP status: 402
Last checked: 2026-11-04T04:04:02.516Z
Reachability: 92.3% over 13 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{}

Output schema

null