Private Function F(ByVal number As Long) As Long
    F = Choose(number, 1, 2, 6, 24, 120, 720, 5040, 40320, _
        362880, 3628800, 39916800, 479001600)
End Function

1. What does this code do?
2. What's wrong with this technique (aside from the function's name which is intentionally obscure so it's not too obvious what the code is doing)?
3. Can you think of an alternative approach that's also easy to understand?
4. Which version is better?