Covid-19 spread
A Street has 13 houses in a row. Some residents in the first house tested positive for Covid-19. The virus spreads in 2 ways: It can spread to the next house or jump directly to the third house. Residents of house two can get infected in only one way, house 3 in two ways, house four in 3 ways, house 5 in five ways, and so on. If the virus progresses from left to right, how many ways can house 13 be infected?
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