## How do I find the nth term of this sequence?

Complex numbers, rational functions, logarithms, sequences and series, matrix operations, etc.
rogermiranda
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### How do I find the nth term of this sequence?

I have the sequence 2,8,26,80,242
So b sub n = 6,18,54,162
b sub 1 = 6
r = 3
using the geometric formula I have 6 times 3^(n-1).
Now I am stuck? What are the next steps? Please help!

Martingale
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### Re: How do I find the nth term of this sequence?

rogermiranda wrote:I have the sequence 2,8,26,80,242
So b sub n = 6,18,54,162
b sub 1 = 6
r = 3
using the geometric formula I have 6 times 3^(n-1).
Now I am stuck? What are the next steps? Please help!

3,9,27,81,243..

=$3^1,3^2,3^3,3^4,3^5,...$

your sequence is one less per term

so the nth term is $3^n-1$

stapel_eliz
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rogermiranda wrote:I have the sequence 2,8,26,80,242
So b sub n = 6,18,54,162

How does your "so" statement relate to the given sequence?