Factorial Calculator
Free Online Factorial Calculator with Step-by-Step Solutions
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Calculate Factorial
Understanding Factorials
Definition & Properties
A factorial (n!) is the product of all positive integers up to n.
n! = n × (n-1) × (n-2) × ... × 2 × 1
Special Cases:
0! = 1 (by definition)
1! = 1
Negative numbers: undefined
Non-integers: calculated via Gamma function
Common Applications
Probability & Statistics
Combinations (nCr)
Permutations (nPr)
Sequence Analysis
Algorithm Complexity
Number Theory
Example Calculations
3! = 3 × 2 × 1 = 6
4! = 4 × 3 × 2 × 1 = 24
5! = 5 × 4 × 3 × 2 × 1 = 120