Notation question about Markov Chains: "the $j$th component of $\mathbf{s}Q^n$ is $P(X_n = j)$"

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I have a question about the following passage from my book (see screenshot below).

The book says: the $j$th component of $\mathbf{s}Q^n$ is $P(X_n = j)$

However shouldn't it say: the $j$th component of $\mathbf{s}Q^n$ is $P(X_n = j \mid \text{given $X_0$ has pmf $\mathbf{s}$})$

It seems to me that $\mathbf{s}Q^n$ does not yield the unconditional distribution of $X_n$ since it depends on how you set the pmf for $\mathbf{s}$.

To get the unconditional distribution $P(X_n =j)$ then you have to let $n \rightarrow \infty$ and you need your chain to settle on something (ergodic is the term maybe).

Can you help clarify my confusion? Thanks for your patience and help.


Passage from book

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