Permutation Functions for calculating ALL possibilities

So i'm putting myself on the line here with my colleagues for this question because I'm confident in the belief that Excel Wizards have an innate understanding of math in the realm of real world applications, more so than scientific academics (which many of the community are to begin with, but I believe Excel compliments scientific thought for the real world rather formidably.
So here it goes:
This question is essentially about Electromagnetism but as mentioned before i'm sure that you guys could answer this blind folded without ever hearing of V=IR.

I took a part a few amplifiers (fenders) because i'm interested in using the high quality solid state components (specifically resistors). The great news is that if you look up a schematic of any amp it labels each resister and shows their value right off the bat. Column 1, column 2 in my mind.

What I want to be able to do is input all of the resistors on the PCB (printed circuit board), assigning a name (R1, R2,... etc) in one column and their corresponding resistance in another. I then want Excel to calculate ALL of the possible resistance value that can be made with the resistors in this closed set. this is easy, however, you have to remember that resistance has a few equations to govern them:
R1+R2..Rn=Rtotal when placed in SERIES
[(R1+R2...Rn)/n]=Rtotal when placed in PARALLEL

Kind of changes the game, no? Especially when you also realize that you can have a group of resistor in parallel and then put them in series with another, or in series with another group of resistors in parallel...you get where I'm going. Because you essentially have 3 equations to apply, you can't abide by the permutation rules which state if you have, say, 3 values, it will have the factorial ! amount of permutations (6), but since there are a few different ways to combine the values the true amount of permutations is 14 (i think, may be off by +/-1)

Once I have this function (I'm pretty positive the true answer will be a CHAIN of functions), I can easily have excel sort ALL the possibilities so I can easily see which combination of resistors will:
1) Give me the desired Resistance
2) use the least amount of my resistor stock

To clarify #2, If my desired resistance is 100KOhms, there are going to be more than one combination that results in this resistance, but who'se going to put 3 50-Ohm resistors in parallel to get a total of 50-Ohms when you could just use ONE of the 50-Ohm resistors in series. I'm cheap, I want to be able to conserve my resistors (They're vintage!)

I can easily do a column sort to find the most optimal combination, but I don't know what function chain can get me there.

Ive talked to some electrical engineers and they can't get it. And when I say "can't" i mean they can't find the answer QUICKLY (quickness is what excel is all about, right? Which is why we're all awesome). Like i said, you excel wizards are in understanding that IF its possible tio be calculated, THEN Excel can just do it better/quicker.

I know how i can calulate this out the long way as i'm not in the 4th grade, but I KNOW theres a quick trick.

EX. How do u calculate winning the lotto? A 3rd grader will write out 6/49,5/48,4/47.....1/44- the add, then divide etc etc..when it could have been as easy as 49!/(49-6)!. Thats the "tricl" i'm looking for here.

Thanks guys you're all the best.

coorection: "If my desired resistance is 100KOhms, there are going to be more than one combination that results in this resistance, but who'se going to put 3 50-Ohm resistors in parallel to get a total of 50-Ohms when you could just use ONE of the 50-Ohm resistors in series."

i did not mean 100kOhms I meant 50-Ohms as the desire resistance. Sorry!