Factorial function using GMP

Factorial

That's 6 factorial over 4 factorial times 6 minus 4 factorial.

Our JavaScript interpreter is going to have to compute the value of 6 factorial, a function call within a function call within a function call.

Our factorial function is going to be recursive, and every recursive function needs a base case, a time when it stops.

3 factorial over and then 3 minus 2 factorial.

Here I've written JavaScript code to compute the factorial function, and this code is correct.

In fact, especially in something like factorial, if I'm asking for the factorial of 10, we're going to call this function a large number of times.

That's 7 factorial.

Five factorial is 120.

It actually computes factorial.

So that's 2 factorial.

And then 2 factorial.

We could write it as n factorial it s a lower case n n factorial over n minus k factorial.

So in general, we said, n choose k, that is equal to n factorial over k factorial times n minus k factorial.

Now if this weren't an anonymous function but were instead a recursive function like factorial, we might be able to see the bug with only one.

Well, that's just 1 factorial.

This would be 9 factorial.

So in this situation that would equal 8 factorial over 3 factorial times what?

So now 4 times 3 factorial, that's just 4 factorial over s to the fifth.

To do so, I'm going to make a recursive function called surprise, surprise factorial that's going to compute the value.

So the function that we are computing here is mathematically called factorial, and it's sometimes written with an exclamation point.

Here's one way to define factorial.

8 minus k times 5 factorial.

But we're going to have to consider 4 factorial times 5 factorial paths before we discover that.

The 3 largest components of 7 factorial.

We've got this five factorial, this bang.

So in this case, n factorial was 7.

And then what was n minus k factorial?

The exclamation mark often means factorial in mathematics.

He can't remember the value of five factorial.

It's n times the factorial of n 1.

Plus x to the fourth over 4 factorial.

At the end of absolute value or Fibonacci or factorial or almost any function or procedure we want to return with the final value, return an arbitrary expression that becomes the value of the function.

The Hillis algorithm. 10 factorial gives you that number.

7 factorial will be 7 times 6 times 5.

And similarly, 6 well, 6 is also 3 factorial.

So 7 minus 3 is 4, so 4 factorial.

There's the global frame. There's our call factorial 6.

It essentially becomes 9 factorial times 2 times 1.

Things like factorial, s and tmp are all identifiers.

But all this is saying is you start doing the n factorial, but you only do the first 3 components of the factorial.

So we're just taking all the even terms. x to the eighth over 8 factorial minus x to the 10th over 10 factorial.

But we only took the first 3 of the factorial.

To write the first k of n factorial. Why sure.