Geometric progression Calculator

Calculates the n-th term and sum of the geometric progression with the common ratio.

initial term a
common ratio r
number of terms n
    1. n=1,2,3...

the n-th term an
sum Sn
Geometric progression
[1-2] /2Disp-Num
[1]  2018/03/17 07:43   Female / Under 20 years old / High-school/ University/ Grad student / Not at All /
Purpose of use
I was looking for a calculator to find the common ratio of a sequence when given the first 3 numbers of that sequence. I can''t seem to find one of those...
[2]  2013/03/23 03:56   Male / 50 years old level / Others / A little /
Purpose of use
Von Neumann probe estimate. 400 billion stars in the galaxy, how many iterations before a reproducing probe produces a number equivalent to one probe per star. Assume original probe produces 1 per month until T is reached. Every probe after that does the same once its arrived. Average travel time between stars assume 50 years.


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