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Permutations (nPr)

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

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Our latest check (2026-10-11)

Answering
Yes — valid x402 payment terms
Time to answer
434 ms
Price
$0.004 per call
Paying buyers, last 30 days
1 (directory's own records)
Paid calls, last 30 days
1
Category
Unclassified
Address
https://combinatorics.openverbs.com/v1/permutations

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