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[bo198214]

How are you computing the Carleman matrix?

Actually I use a direct formula, I thought that was the fasted method. But it seems that I am wrong:

Code:

C = Matrix([ [log(b)**n/factorial(n)*sum([binomial(m,k)*k**n*(b**x0)**k*(-x0)**(m-k) for k in range(m+1)]) for n in range(N)] for m in range(N)])

(Where N is the size, b is the base and x0 is the shift)
I also always used precision 1000 but that does not stretch the time in that amount.
I really dont know why it takes so long.

Why is in your Carleman matrix output only little precision while you put in 512?

I use iterative matrix multiplication,

I am not sure how it works. Can you give just the basic idea?