The sum of an arithmetic sequence can be found using the formula $S_n = \frac{n}{2}(a_1 + a_n)$, where $S_n$ is the sum of the first $n$ terms, $a_1$ is the first term, and $a_n$ is the $n$-th term.
In this case, we have $n = 22$, $a_1 = -1$, and we need to
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