Choosing elements out of set of elements ( ) and disregarding their order is the definition of combinations.
This is a little complicated, i'll try to explain as best i can.
Say I have n different numbers,
I wish to find the summation of every possible way of multiplying different numbers together.
For clarification: if I would want:
If i would want:
Basically, I just need a function that gives this result.
Except you obviously haven't read my post at all. That's not what I'm after. I'm fairly sure I explained what I'm looking for fairly clearly.
Ok, you've shown how many different terms the function will have in terms of x and n. It isn't a formula that will calculate the value of each term and add them together.
Could somebody please read my post and help me with this?