Trick or Treat Street
You are going trick or treating on a special, but slightly mathematically awkward street called Trick or Treat Street. On the first house you visit, you get one piece of candy. When you knock on the second door and say "Trick or Treat", the person gives you two pieces of candy. At the third house, you receive three pieces of candy. If Trick or Treat Street has 20 houses on it and you visit all of them, and this pattern continues, how many pieces of candy will you receive in all?
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