Problem:
Consider the arithmetic sequence defined by $a_1=-\frac{7}{6}$, and $a_n=a_{n-1}+-\frac{58}{7}$ for $n > 1$. Compute the nth partial sum, $S_n=\sum_{k=1}^n a_k$, where $n=25$.
Answer:
$-\frac{105625}{42}$
{'source': 'AMPS', 'file': 'amps/mathematica/algebra/arithmetic_series/36084.txt'}