how to refactor nested for loop into smaller for loop assume each of them independent?

[Ho Yeung Lee]

I updated the code in msdn forum,

I calculated from the end of file 
Discover file 4550 takes a long time to run,

Assume it runs a whole day a file, 4550 days I guess need 12 years to finish full combination if only run at home.


Hope Python sympy can be faster than cmaple in Amazon instance