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The Hardy-Littlewood circle method (with Vinogradov's improvement) states that given a set $A \subset \mathbb{N}\cup \left \{ 0 \right \} $ and given a natural number $n$, if we consider the sum:

$$f(z)=\sum_{r\in A,\; r\leq n} z^r$$

then

$$ \text # \left \{ (r_1,r_2,..,r_k)\in A^k: \ r_1+r_2+...+r_k=n \right \}=\int_{0}^{1} f^{k}(e(\alpha )) e(-n\alpha )\text d\alpha$$ $$e(\alpha)=\text{exp}(2\pi i\alpha)$$

However, this representation counts permutations, for example if we consider $A=\mathbb{Z}^{+}$ then

$$S(n,k):=\int_{0}^{1} f^{k}(e(\alpha )) e(-n\alpha )\text d\alpha$$

It gives me the "partitions" of $n$ into $k$ parts, however we know that the partitions of 6 into three parts are 3:

$$(2,2,2), (1,2,3), (1,1,4)$$

But $S(6,3)=10$, since the function counts the permutations of the three representations. (2,2,2) does not have different permutations, so add 1, (1,2,3) gives me six different permutations adding another 6 and finally (1,1,4) has three different permutations adding 3, which in total are the 10 that I get from $S(6,3)$.

My question is this: Is there a way to modify the Circle Method so that the function obtained tells me the number of representations but without counting permutations?

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    $\begingroup$ To me, it seems unlikely. You would need to find a subtitute for $f$ with singularities only at one of each permutation of each partitition - or perhaps quotienting the space in some way to remove the multiplicity coming from permutations. Distinguishing between such permutations in an analytic way seems difficult. "Fixing" this method for your needs would basically constitute a new method, would be my guess. $\endgroup$ Commented Jun 3 at 11:28
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    $\begingroup$ You can prove using Ferrer diagram that the number of ways to partition some number into $\le k$ components is the same as the number of ways to partition some number into arbitrarily number of components, each $\le k$. $\endgroup$
    – TravorLZH
    Commented Jun 5 at 0:31

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