2. The factorial of positive integers is the product of all positive integers less than or equal to this number, and the factorial of 0 is 1. The factorial writing of natural number n! . In 1808, Keston Kaman introduced this notation;
3. The factorial of positive integers is the product of all positive integers less than or equal to this number, and the factorial of 0 is 1.
Extended data:
Introduction to factorial:
For general plural,? The product of congruences of all modules n less than or equal to │n│ means that its real part and imaginary part must meet certain conditions.
n! The factorial of a fraction in which n is a decimal or cannot be written as an integer is called generalized factorial. In addition, it should be noted that this factorial cannot be written as1× 2× …× n.
Factors are mainly used in the calculation of permutation and combination, and gamma function and gamma function are also related to factorial.
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