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Can you solve the Leonardo da Vinci riddle? - Tanya Khovanova

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TEDEd Animation

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You’ve found Leonardo da Vinci’s secret vault, secured by a series of combination locks. Fortunately, your treasure map has three codes: 1210, 3211000, and… hmm. The last one appears to be missing. Can you figure out the last number and open the vault? Tanya Khovanova shows how.

The number of digits of an autobiographical number equals the sum of its digits. There are no 3-digit autobiographical numbers, but there are 3-digit numbers whose sum of digits is also 3. How many are there?

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Tanya Khovanova
  • Director Outis
  • Narrator Addison Anderson
  • Script Editor Alex Gendler
  • Animator Nemanja Petrovic
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Associate Producer Bethany Cutmore-Scott, Elizabeth Cox
  • Fact-Checker Brian Gutierrez

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