I am looking for whether there is any notation for the $k$-partition number of $n$ where the partitions must include some summand $s$.
An example of the kind of notation I am looking for is $P_k^s(n)$. To exemplify what I mean, see this:
$$P_3^2(6) = |\{ (1,2,3), \ (2,2,2) \} | = 2$$
That is, there are only two $3$-partitions of $6$ that have at least one summand being $2$. I don't quite like my notation here, but that's besides my question. Does anybody know if there's any pre-established, if not conventional, notation for this?
EDIT:
Although $P_k^s(n) = P_{k-1}(n-s)$, and although this fact is present in my paper, I need an intermediate expression for notational/proof reasons.