uhmmm it's not much clear, I have not fully understood what you mean.
for example imagine if we have the program xxx.exe that performs a custom compression (it's probably not a math formula but it's ever something math related), without debugging/analysis it you can't know where is located this function in the executable.
instead if you refer to the usage of the functions located in an executable without reversing them (so like "exporting" them into your project) then we arrive to that thread I posted on xentax:
http://forum.xentax.com/viewtopic.php?f=13&t=3794that is also something possible with quickbms and the calldll function, but in any case a minimum of debugging is ever needed.