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Second attempt

We can compute the logistic map using finite, but arbitrarily large binary expansions. Notice that this is different from multiple precision, as the size of a multiple-precision number is fixed in advance. This is
1.
reliable, but
2.
unfeasible in terms of time and space consumption.
For n > 10, the computation of fn(x0) takes more than I was patient to wait for. Thus, this is even worse than rational arithmetic. It is easy to see why this is the case. If x has a binary expansion with n digits, then 1-x has often n digits as well. But if x and y have m and n digits then xy has mndigits. Thus, fn(x0) has approximately 2n m digits if x0has m digits.



Martin Escardo
2000-10-02