Counting
Combinatorics
Permutations and combinations of r items drawn from n, in exact arbitrary-precision arithmetic.
Whole numbers with 0 ≤ r ≤ n ≤ 200. Blank fields and exponent notation are refused, not read as zero.
Try
- n!
- 3628800
- P(n,r)n! / (n-r)!
- 720
- C(n,r)n! / (r!(n-r)!)
- 120