How to create a formula to calculate the different combinations of money amount distribution?

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Let's say that you have an amount of 100 euros and you want to distribute all of it between 3 persons without taking into consideration the decimal fractions of the euro.

If we started with some simple scenarios, then we could say:

If instead of 3 we had just one person and since we have to distribute all of the amount then we would have just a single case.

If we had 2 persons then, I guess, that we would have 100 different combinations, of distribution among the persons.

For let's say 3 persons, I have tried to solve it with Binomial coefficient, since we are talking only about integers, like this:

C(n,r) = C(100,3) = (100!)/(3!(100−3)!) = 161.700  

But the result seems pretty high and I guess that this is probably because this formula takes into consideration that every n is different, or something like that.

However, in a problem where n is currency unit and there is also the rule of distributing all of the amount, which means that we want to exclude the combinations like
1€-1€-1€,
1€-1€-2€,
... then to be honest, I do not know how to approach this problem to create a formula, so any ideas would be much appreciated.

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Let "o" represent $1$ Euro and let "|" represent divisor. It is obvious that we need $2$ divisors and applying repeated permutation into "ooo...o||" ($100$ "o" and $2$ divisors) gives us $\binom{102}{2}=5151$ different distribution. $$\\$$ For example, "ooo...o|ooo...|ooo" ($51$ "o" on left, $46$ "o" on middle, $3$ "o" on right) is $51$ Euro for $1^{st}$ person, $46$ Euro for $2^{nd}$ person and $3$ Euro for $3^{rd}$ person.