The Mandelbrot Set and Julia Sets

Scalings in the Mandelbrot Set - Component Diameter

How can we measure the sizes of the 2-cycle, 4-cycle, 8-cycle, 16-cycle, ... components of the period-doubling cascade?

The diameter of the 2-cycle component is the distance between where that component attaches to the big cardioid, and where the 4-cycle component attaches to that component.

Similarly, we can think of the diameter of the 4-cycle component as the distance between where the 4-cycle component attaches to the 2-cycle component, and where the 8-cycle component attaches to the 4-cycle component.

The same kind of measurement can be made all along the period-doubling cascade.

In general, call cn the point of attachment of the 2n-cycle and 2n-1-cycle components in the period-doubling cascade.

Careful numerical experiments give these values:

c1 = -0.75
c2 = -1.25
c3 = -1.3680989394 ...
c4 = -1.3940461566 ...
c5 = -1.3996312389 ...
c6 = -1.4008287424 ...
c7 = -1.4010852713 ...
c8 = -1.401140214699 ...
c9 = -1.401151982029 ...
c10 = -1.401154502237 ...
...

The diameter of the 2n-cycle component in this cascade is |cn+1 - cn|.

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