You have a pile of 1 x 2 unit dominoes. There's one way to tile a 1x2 area, 2 ways to tile a 2x2 area, 3 ways to tile a 3x2 area, and 5 ways to tile a 4x2 area. How many ways are there to tile a 5x2 area with your 1x2 domino tiles?

Answer 1

I find 8.

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