Counting the number of integer partitions

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We start with a fixed partition of $[n]$, namely $(1,1...,1)=(1^{(n)})$.

We define an operation, say F, that takes two numbers within the partition and adds them up. So the first step leads to the partition $(2,1^{(n-2)})$.

Repeating it another time, we get two possibilities $(3,2,1^{(n-5)})$ and $(2,2,1^{(n-4)})$

It is clear that this process will end after $n-1$ steps when all the numbers are added up, leaving us with the partition $(n)$.

What I'm interested in finding is the total number of such partitions for a particular $n$.

I initially tried variants of Bell numbers, but to no avail. I don't think there's a direct link to them, but I would be happy if anyone could prove me wrong on that. Writing the sequence out by hand, I obtain $$1,2,3,5,8,11,15,22....$$I couldn't find an obvious pattern and it seems too unwieldy to manipulate by hand.

If anyone can point me towards the right direction, that would really be great! Thank you!

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The answer is right there on Wikipedia! Duh-oh! I'm not certain how to close this question, so I will just write a short answer and accept it! Do let me know if I should be doing something else instead.

So, accordingly, there's no known closed-form expression for the partition function, but there exists generating functions and recurrence relations for it. And that's the answer I was looking for!

I was trying to find the number of possible partitions obtained from applying $F$ to $(1^{(n)})$ $k$ times, but this direction doesn't seem that fruitful.

Thank you to all who looked at and answered my query!