• karpintero@lemmy.world
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    3 days ago

    Some interesting bits from the article:

    Anon is credited as the first author in the paper

    Computers are able to calculate superpermutations for n = 4 and n = 5 but not for anything beyond that.

    Since the series in question has 14 episodes, it would take 93,884,313,611 episodes to see all possible combinations. Or roughly 4 million years of non-stop viewing.

    • remi_pan
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      3 days ago

      Is this number the exact result or a lower bound ?

      • karpintero@lemmy.world
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        3 days ago

        Lower. It caught their attention because a science fiction author had come up with upper bound, which the article notes was also bizarre.

        Houston had just learned that Australian science fiction author Greg Egan had found a new maximum length for the shortest superpermutations

      • Hugin@lemmy.world
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        3 days ago

        You can watch it again in a different order.

        This is mostly about minimizing the number of viewings. So for a 3 episode series you can get order ABC and order BCA in 4 viewings instead of 6 by watching in order ABCA.

        • Evotech@lemmy.world
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          3 days ago

          But you don’t start from the beginning each time.

          More of a philosophical question I suppose, not mathematical

          • L0rdMathias
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            2 days ago

            There is not really a concept of a “true beginning” in this type of mathematics. The beginning is defined to be wherever you start.

            Where does a circle start and end? Every point on a circle is both the beginning and the end of that circle. The math of permutations and combinatorials are closely related to the geometry of circles and because of that they take on a lot of similar properties. Another way to phase this question is “If I have a set of beads that are all the same size but different colors, and I want to chain multiple beads of different colors together using specific limited pallets of colors to make bracelets, what is the bracelet with the smallest size where after one rotation around the bracelet I will have seen every possible combination of the set of colors used in the pallet for that bracelet.” If that sounds confusing, it’s because it is.