superfac9.java

http://bearnol.is-a-geek.com/superfac9.java
(with thanks to Dario Alpern)

Explanation of input format:

1) You can either enter just a (denary) number in the normal way:
eg, 123 or 7654321 or

2) you can enter a formula using the following operators by prefixing with f or F:
+ for addition
- for subtraction
* for multiplication
/ for integer division
% for modulo division
^ or # for exponentiation
[ or { or ( for open parenthesis (nestable)
] or } or ) for close parenthesis (nestable)
eg, f2#700+1 or F2#(2#12)+1 or

3) you can enter a randomly generated number of approximate size 2^n, by using the syntax rn or Rn, where n is an integer:
eg, r200 or R1000


[please note, in particular, the speed with which algebraic factors are found]
Enjoy!