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Cycles in run-length encoding
code-golfnumbersequence
Related.
Consider some binary sequence, using 1 and 2, e.g.:
1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 1 ...
Let's write down the run lengths of that:
1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 1 ...
_ _ ____ ____ _ _ _ ____
1, 1, 2, 2, 1, 1,...