• zipsglacier@lemmy.world
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    1 year ago

    There are tons of them! For example, the class of numbers n such that there is a Platonic solid made of n-gons. This class only has the numbers 3, 4, and 5. You can get other examples any time there is an interesting mathematical structure with only finitely many examples.

    • CanadaPlus@lemmy.sdf.orgOP
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      1 year ago

      Well, yes, obviously. I was hoping for something number-theoretic, though. Let me reword the title.

      • zipsglacier@lemmy.world
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        1 year ago

        Haha, ok, how about numbers n such that there are nontrivial solutions to a^n + b^n = c^n

        My point is that interesting (non-)existence results give examples of the type I thought you were asking for.

        • CanadaPlus@lemmy.sdf.orgOP
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          1 year ago

          Oh yeah, Fermat’s Last Theorem. I bet I would have thought of that right away if I was a bit older. The Wiefrich primes came up elsewhere here, and they have a kind of similar background.

          Thanks for the answers!