Comment l'utiliser (3 étapes)
- Select a mode: n^r for ordered sequences, or nHr for unordered selections (both allow repeats).
- Enter n (types) and r (length / picks). Default values show a common PIN example.
- Switch to Approx when Exact is too large to display. Copy the URL to share exactly what you see.
Result
Digits and scientific notation help you understand scale even when the exact integer is too large to display.
History
Growth chart (n fixed, r increases)
Shows how fast counts grow as r increases with n fixed. Blue: n^r. Green: nHr (multichoose).
FAQ
Quelle est la différence entre permutations et combinaisons avec répétition ?
Permutations with repetition count ordered sequences (AB ≠ BA). Combinations with repetition count unordered selections (AB = BA), allowing repeats.
Comment calcule-t-on nHr ?
nHr can be rewritten as a binomial coefficient: nHr = C(n+r-1, r) = C(n+r-1, n-1).
r peut-il être supérieur à n ?
Yes. With repetition allowed, you can pick the same type multiple times, so r > n is valid.
Quand faut-il utiliser Exact ou Approx ?
Use Exact for manageable sizes when you need the full integer. Use Approx when the integer is huge; you still see the digit count and scientific notation.
Comment ce calculateur traite-t-il 0^0 ?
This tool defines n^0 = 1 and treats 0^0 as 1, since the empty sequence is counted as one outcome.