Definition 4.1.2: Series, Partial Sums, and Convergence
Let {a n} be an infinite sequence.
- The formal expression is called an (infinite) series.
- For N = 1, 2, 3, ... the expression S N = is called the N-th partial sum of the series.
- If lim S N exists and is finite, the series is said to converge.
- If lim S N does not exist or is infinite, the series is said to diverge.