Julia Sets and the Mandelbrot Set

Exercise Answers

1. (a) Here is what we find.
The largest midget on the left branch has cardioid with cycle number 4. Going toward the point where the antenna spokes meet, we find 7 and 10.
The largest midget on the right branch has cardioid with cycle number 5. Going toward the point where the antenna spokes meet, we find 8 and 11.
The largest midget on the bottom branch has cardioid with cycle number 9. Going toward the point where the antenna spokes meet, we find 12 and 15.
Patterns
    Going along each spoke, the cycle numbers go up by 3, the period of the disc to which the antenna is attached.
    The largest midgets on the spokes (excluding the one attaching the antenna to the body of the Mandelbrot set) have cycles 4 = 3 + 1 and 5 = 3 + 2.
    The largest midget on the spokes attaching the antenna to the body of the Mandelbrot set has cycle 9 = 3*3.
A reliable way to find the cycles is to first magnify the midget Mandelbrot set sufficiently to be sure the pointer is in the cardioid, then shift-click or right click. The right window shows the cycle to which the iterates of 0 converge.

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