Factorial (n!)
! = 3,628,800
Permutation P(n, r) = n! / (n-r)!
P( , ) = 720
Combination C(n, r) = n! / (r! × (n-r)!)
C( , ) = 120
Factorial Reference
Formulas
- n! — product of all integers from 1 to n
- P(n,r) — ordered arrangements of r items from n
- C(n,r) — unordered selections of r items from n
- Maximum input is 170 (JavaScript number limit)
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