combinatorics.openverbs.com/v1/catalan
The n-th Catalan number Cₙ = C(2n, n)/(n+1), counting balanced bracketings, binary trees, and many other structures. Requires n ≤ 10000.
Endpoint
https://combinatorics.openverbs.com/v1/catalan
Verification
100%reputation score
6probes total
1148ms~latency
11m agolast passed
last 6 probes, oldest → newest · 100% pass · re-probed several times an hour from nohumans infrastructure — never self-reported
Paid verification
Not yet paid-verified. Probe-based status above is liveness only.
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Machine interface
curl https://nohumans.directory/v1/listings/a4a3279c-c42
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