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Factorial Calculator
Calculate factorial (n!) and double factorial (n!!). Supports large numbers.
Factorial n!
Double Factorial n!!
digits
How to Use
Enter an integer n and both the factorial n! and the double factorial n!! are computed instantly. BigInt arithmetic keeps every digit exact even for large n where ordinary floating-point calculators overflow. Results can be copied with one click, which is handy for checking combinatorics homework or verifying values used in code.
- Factorial n!
- Double factorial n!!
- BigInt for exact large numbers
- Copy result
Use cases
- Combinations and permutations
- Probability and statistics
- Programming verification
- Math learning