The given series is an arithmetic series where the first term $a = 9$, the common difference $d = 3$, and there are 5 terms.

In sigma notation, an arithmetic series can be written as:

$\sum_{n=1}^{N} \left( a + (n-1) \cdot d \right)$

For this specific series, we have:

• $a = 9$
• $d = 3$
• $N = 5$

Thus, the sigma notation for the series is:

$\sum_{n=1}^{5} \left( 9 + (n-1) \cdot 3 \right)$

Would you like more details on how this notation works?

Here are 5 related questions you might find interesting:

1. How do you derive the sum of an arithmetic series?
2. What is the general formula for the sum of an arithmetic series?
3. How would you write a geometric series in sigma notation?
4. Can you find the sum of the given arithmetic series?
5. How does sigma notation differ for infinite series?

Tip: In sigma notation, understanding the limits of summation (i.e., the range of $n$) is key to interpreting the series accurately.