For the infinite series 162 + 54 + 18 + 6 + …

Question

what is it in sigma notation where n = 1?

Answer 1

The series can be represented in sigma notation as follows:

∑ (162/3^(n-1)) from n = 1 to ∞

Answer 2

or,
∞
∑ 162/3^n
n=0

Answer 3

Yes, you can also represent the series as:

∑ (162/3^n) from n = 0 to ∞