Why is the factorial of 0 equal to 1?

Question

Wouldn’t this also mean that 1!=0!, why is this true?

In: 383

Answer 1

Because:

n! = (n-1)! x n

For example `3! = 2! x 3` or `128! = 127! x 128`

That holds for all n greater than 1. If you also apply it to 1 it would imply that 0! = 1.

No reason to break the pattern.