Factorial Function for N between 171 and 681

This function calculates an approximate value for the Factorial function for numbers between 171 and 681.

The routine overflows for N > 681. I can verify up to N = 253 against an HP 32S II Scientific calculator.

Anyone is free to use the algorithm, but there are no guarantees, implied or otherwise. The author asks only that a comment be added to your source code specifying my name (Edward Ardzinski) and that the algorithm was obtained from FreeVBCode.com