• affiliate@lemmy.worldOP
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      9 months ago

      it’s the “order type” of a well ordering on a set. so, given a set X with a total ordering R, type(X,R) is the unique ordinal isomorphic to (X,R)

      • bort@feddit.de
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        9 months ago

        what’s with the square at the end? isn’t that usually for proofs?

        • affiliate@lemmy.worldOP
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          9 months ago

          yeah but sometimes when the textbook authors are feeling particularly mischievous they’ll just put them in random places. and sometimes they’ll even skip the proofs but keep the square.

      • Lem Jukes@lemm.ee
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        9 months ago

        Give it up for op actually out here answering questions like a real live teacher.