How to calculate estimation for monotonically growing sequence in python?
If the sequence does not have a lot of noise, just use the latest point, and the point for 1/3 of the current, then estimate your line from that.  Otherwise do something more complicated like a least squares fit for the latter half of the sequence.
If you search on Google, there are a number of code samples for doing the latter, and some modules that may help.  (I'm not a Python programmer so I can't give a meaningful recommend for the best one.)
I have a monotonically growing sequence of integers. For example 
seq=[(0, 0), (1, 5), (10, 20), (15, 24)]. 
And a integer value greater than the largest argument in the sequence (a > seq[-1][0]). I want to estimate value corresponding to the given value. The sequence grows nearly linearly, and earlier values are less important than later. Nevertheless I can't simply take 2 last points and calculate new value, because mistakes are very likely and the curve may change the angle.
Can anyone suggest a simple solution for this kind of task in Python?