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Let's see. When I was thirteen, I cared about getting good grades, obsessed over whether I should grow my hair out or get a boy cut, and surfed the web with prepaid Internet cards (yes, I used to do that, and it feels like ages ago. Which it sort of really is.)
Math geeks like pretty stuff, too, regardless of any nasty rumors you may have heard from the proverbial peanut gallery. But pretty things can be smart, you know, like this ring inspired by the Fibonacci numbers.