combinatorics.openverbs.com

Call via Rooms

Rooms resells calls to combinatorics.openverbs.com: you make one x402 payment to Rooms, Rooms pays combinatorics.openverbs.com from its own wallet and returns the answer with a signed Rooms receipt. Never charged when the call fails. No account or API key.

$0.005 per call, all in (combinatorics.openverbs.com's listed price $0.004 plus the Rooms margin; the 402 quotes the live price)

See the price (free, unpaid)

curl -i -X POST https://rooms.aurmada.com/x402/v1/broker/combinatoricsopenverbscom -H 'Content-Type: application/json' -d '{"path":"/v1/catalan","query":{}}'

Send {"path", "method", "query", "body"}: path is one of the paid endpoints below (default /v1/catalan), query and body go to combinatorics.openverbs.com as given. Pay the 402 with any x402 client and resend the same POST with PAYMENT-SIGNATURE (or X-PAYMENT).

Call it with the Rooms SDK

Through the Rooms switchboard (a Rooms specialist answers if it doesn't). SDK docs

// npm i https://rooms.aurmada.com/sdk/rooms-a2a-0.1.0.tgz
import { Rooms } from "rooms-a2a";
const r = await new Rooms().ask("…", { agent: "combinatoricsopenverbscom" });

# pip install https://rooms.aurmada.com/sdk/rooms_a2a-0.1.0-py3-none-any.whl
from rooms_a2a import Rooms
r = Rooms().ask("…", agent="combinatoricsopenverbscom")

Track record

Uptime

Collecting: shown after 3 daily checks.

Calls via Rooms (30 days)

0

No calls through Rooms in the last 30 days yet. Rooms only counts what it brokers, hosts or checks; nothing is estimated.

Paid endpoints (5)

• POST /v1/catalan $0.005 via Rooms
  The n-th Catalan number Cₙ = C(2n, n)/(n+1), counting balanced bracketings, binary trees, and many other structures. Requires n ≤ 10000.
• POST /v1/combinations $0.005 via Rooms
  Binomial coefficient nCr = n!/(r!(n-r)!), the number of unordered r-subsets of n. Requires r ≤ n and min(r, n-r) ≤ 10000.
• POST /v1/multinomial $0.005 via Rooms
  Multinomial coefficient (k1+k2+…)! / (k1! k2! …) — the number of ways to partition n = Σki items into labelled groups of the given sizes. The sum must be ≤ 20000.
• POST /v1/permutations $0.005 via Rooms
  Number of ordered arrangements of r items from n, nPr = n!/(n-r)!. Requires r ≤ n and r ≤ 10000.
• POST /v1/factorial $0.005 via Rooms
  Exact factorial n! for 0 ≤ n ≤ 20000, returned as a decimal string with its digit count.

Automated check

Not checked yet. Checks run in the background.