What does ( 0.25)^(3n) converge towards? (EASY Q)

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Really quick question here:

I want to find the sommation of f(x) = 0.253n for x being a Natural ( N) number going from 0 to infinity.

k1k2n converges towards what, as a general rule?

Where k1, k2 are constants and n= 0,1,2,3 ...

EDIT: NO, not what it converges to, but what the sommation is equal to... as in f(0)+f(1) +f(2) + ...
 
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It's a geometric series isn't it? It's ((1/4)^3)^n. What do you know about the sum of geometric series?
 
Well, I'm looking for = ∑rn-1 for n going from 1 to infinity... But isn't there a formula for where n starts at 0?

I also know that you can play around sith Sn= (1-rn) / (1-r) , but I don't remember/know where this leads to.
 
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I'll help you out. The sum for n=0 to infinity of r^n is 1/(1-r) for r<1. That's the n->infinity limit of your Sn.
 
All right, thanks a lot
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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