17.
Consider the following statements in respect of the expression \( S_{n} = \frac{n(n + 1)}{2} \), where n is an integer:
1. There are exactly two values of n for which \( S_{n} = 861 \).
2. \( S_{n} = S_{-(n + 1)} \) and hence for any integer m, we have two values of n for which \( S_{n} = m \).
Which of the above statements is/are correct?